v31.1.0

[Backport staging] Broaden spec version support (#4016 )
Co-authored-by: Richard van der Hoff <1389908+richvdh@users.noreply.github.com> Fixes https://github.com/matrix-org/matrix-js-sdk/issues/3915.
2024-01-19 13:44:03 +00:00 · 2024-01-18 17:40:07 +00:00 · 2024-01-16 17:36:41 +00:00 · 2024-01-09 17:46:58 +00:00 · 2024-01-08 16:35:30 +00:00 · 2024-01-08 15:34:49 +00:00
208 changed files with 14710 additions and 4946 deletions
@@ -1,7 +1,7 @@
-*                         @matrix-org/element-web
-/.github/workflows/**     @matrix-org/element-web-app-team
-/package.json             @matrix-org/element-web-app-team
-/yarn.lock                @matrix-org/element-web-app-team
+*                         @matrix-org/element-web-reviewers
+/.github/workflows/**     @matrix-org/element-web-team
+/package.json             @matrix-org/element-web-team
+/yarn.lock                @matrix-org/element-web-team
 /src/webrtc               @matrix-org/element-call-reviewers
 /src/matrixrtc               @matrix-org/element-call-reviewers
 /spec/*/webrtc            @matrix-org/element-call-reviewers
@@ -0,0 +1,28 @@
+name: Sign Release Tarball
+description: Generates signature for release tarball and uploads it as a release asset
+inputs:
+    gpg-fingerprint:
+        description: Fingerprint of the GPG key to use for signing the tarball.
+        required: true
+    upload-url:
+        description: GitHub release upload URL to upload the signature file to.
+        required: true
+runs:
+    using: composite
+    steps:
+        - name: Generate tarball signature
+          shell: bash
+          run: |
+              git -c tar.tar.gz.command='gzip -cn' archive --format=tar.gz --prefix="${REPO#*/}-${VERSION#v}/" -o "/tmp/${VERSION}.tar.gz" "${VERSION}"
+              gpg -u "$GPG_FINGERPRINT" --armor --output "${VERSION}.tar.gz.asc" --detach-sig "/tmp/${VERSION}.tar.gz"
+              rm "/tmp/${VERSION}.tar.gz"
+          env:
+              GPG_FINGERPRINT: ${{ inputs.gpg-fingerprint }}
+              REPO: ${{ github.repository }}
+
+        - name: Upload tarball signature
+          if: ${{ inputs.upload-url }}
+          uses: shogo82148/actions-upload-release-asset@dccd6d23e64fd6a746dce6814c0bde0a04886085 # v1
+          with:
+              upload_url: ${{ inputs.upload-url }}
+              asset_path: ${{ env.VERSION }}.tar.gz.asc
@@ -0,0 +1,41 @@
+name: Upload release assets
+description: Uploads assets to an existing release and optionally signs them
+inputs:
+    gpg-fingerprint:
+        description: Fingerprint of the GPG key to use for signing the assets, if any.
+        required: false
+    upload-url:
+        description: GitHub release upload URL to upload the assets to.
+        required: true
+    asset-path:
+        description: |
+            The path to the asset you want to upload, if any. You can use glob patterns here.
+            Will be GPG signed and an `.asc` file included in the release artifacts if `gpg-fingerprint` is set.
+        required: true
+runs:
+    using: composite
+    steps:
+        - name: Sign assets
+          if: inputs.gpg-fingerprint
+          shell: bash
+          run: |
+              for FILE in $ASSET_PATH
+              do
+                  gpg -u "$GPG_FINGERPRINT" --armor --output "$FILE".asc --detach-sig "$FILE"
+              done
+          env:
+              GPG_FINGERPRINT: ${{ inputs.gpg-fingerprint }}
+              ASSET_PATH: ${{ inputs.asset-path }}
+
+        - name: Upload asset signatures
+          if: inputs.gpg-fingerprint
+          uses: shogo82148/actions-upload-release-asset@dccd6d23e64fd6a746dce6814c0bde0a04886085 # v1
+          with:
+              upload_url: ${{ inputs.upload-url }}
+              asset_path: ${{ inputs.asset-path }}.asc
+
+        - name: Upload assets
+          uses: shogo82148/actions-upload-release-asset@dccd6d23e64fd6a746dce6814c0bde0a04886085 # v1
+          with:
+              upload_url: ${{ inputs.upload-url }}
+              asset_path: ${{ inputs.asset-path }}
@@ -0,0 +1,31 @@
+name-template: "v$RESOLVED_VERSION"
+tag-template: "v$RESOLVED_VERSION"
+change-template: "* $TITLE ([#$NUMBER]($URL)). Contributed by @$AUTHOR."
+categories:
+    - title: "🚨 BREAKING CHANGES"
+      label: "X-Breaking-Change"
+    - title: "🦖 Deprecations"
+      label: "T-Deprecation"
+    - title: "✨ Features"
+      label: "T-Enhancement"
+    - title: "🐛 Bug Fixes"
+      label: "T-Defect"
+    - title: "🧰 Maintenance"
+      label: "Dependencies"
+      collapse-after: 5
+change-title-escapes: '\<*_&' # You can add # and @ to disable mentions, and add ` to disable code blocks.
+version-resolver:
+    major:
+        labels:
+            - "X-Breaking-Change"
+    default: minor
+exclude-labels:
+    - "T-Task"
+    - "X-Reverted"
+exclude-contributors:
+    - "RiotRobot"
+template: |
+    $CHANGES
+prerelease: true
+prerelease-identifier: rc
+include-pre-releases: false
@@ -1,7 +1,7 @@
 # Triggers after the "Downstream artifacts" build has finished, to run the
-# cypress tests (with access to repo secrets)
+# matrix-react-sdk playwright & cypress tests (with access to repo secrets)

-name: matrix-react-sdk Cypress End to End Tests
+name: matrix-react-sdk End to End Tests
 on:
    workflow_run:
        workflows: ["Build downstream artifacts"]
@@ -15,7 +15,12 @@ concurrency:
 jobs:
    cypress:
        name: Cypress
-        uses: matrix-org/matrix-react-sdk/.github/workflows/cypress.yaml@v3.79.0
+
+        # We only want to run the cypress tests on merge queue to prevent regressions
+        # from creeping in. They take a long time to run and consume multiple concurrent runners.
+        if: github.event.workflow_run.event == 'merge_group'
+
+        uses: matrix-org/matrix-react-sdk/.github/workflows/cypress.yaml@develop
        permissions:
            actions: read
            issues: read
@@ -23,9 +28,63 @@ jobs:
            pull-requests: read
        secrets:
            # secrets are not automatically shared with called workflows, so share the cypress dashboard key, and the Kiwi login details
-            CYPRESS_RECORD_KEY: ${{ secrets.CYPRESS_RECORD_KEY }}
+            KNAPSACK_PRO_TEST_SUITE_TOKEN_CYPRESS_RUST: ${{ secrets.KNAPSACK_PRO_TEST_SUITE_TOKEN_CYPRESS_RUST}}
+            KNAPSACK_PRO_TEST_SUITE_TOKEN_CYPRESS_LEGACY: ${{ secrets.KNAPSACK_PRO_TEST_SUITE_TOKEN_CYPRESS_LEGACY}}
            TCMS_USERNAME: ${{ secrets.TCMS_USERNAME }}
            TCMS_PASSWORD: ${{ secrets.TCMS_PASSWORD }}
        with:
            react-sdk-repository: matrix-org/matrix-react-sdk
-            rust-crypto: true
+
+    playwright:
+        name: Playwright
+        # We only want to run the playwright tests on merge queue to prevent regressions
+        # from creeping in. They take a long time to run and consume multiple concurrent runners.
+        if: github.event.workflow_run.event == 'merge_group'
+        uses: matrix-org/matrix-react-sdk/.github/workflows/end-to-end-tests.yaml@develop
+        permissions:
+            actions: read
+            issues: read
+            statuses: write
+            pull-requests: read
+            deployments: write
+        with:
+            react-sdk-repository: matrix-org/matrix-react-sdk
+
+    # We want to make the cypress tests a required check for the merge queue.
+    #
+    # Unfortunately, github doesn't distinguish between "checks needed for branch
+    # protection" (ie, the things that must pass before the PR will even be added
+    # to the merge queue) and "checks needed in the merge queue". We just have to add
+    # the check to the branch protection list.
+    #
+    # Ergo, if we know we're not going to run the cypress tests, we need to add a
+    # passing status check manually.
+    mark_skipped:
+        if: github.event.workflow_run.event != 'merge_group'
+        permissions:
+            statuses: write
+        runs-on: ubuntu-latest
+        steps:
+            - uses: Sibz/github-status-action@071b5370da85afbb16637d6eed8524a06bc2053e # v1
+              with:
+                  authToken: "${{ secrets.GITHUB_TOKEN }}"
+                  state: success
+                  description: Cypress skipped
+
+                  # Keep in step with the `context` that is updated by `Sibz/github-status-action`
+                  # in matrix-org/matrix-react-sdk/.github/workflows/cypress.yaml.
+                  context: "${{ github.workflow }} / cypress"
+
+                  sha: "${{ github.event.workflow_run.head_sha }}"
+
+            - uses: Sibz/github-status-action@071b5370da85afbb16637d6eed8524a06bc2053e # v1
+              with:
+                  authToken: "${{ secrets.GITHUB_TOKEN }}"
+                  state: success
+                  description: Playwright skipped
+
+                  # Keep in step with the `context` that is updated by `Sibz/github-status-action`
+                  # in matrix-org/matrix-react-sdk/.github/workflows/end-to-end-tests.yaml.
+                  context: "${{ github.workflow }} / end-to-end-tests"
+
+                  sha: "${{ github.event.workflow_run.head_sha }}"
@@ -14,7 +14,7 @@ jobs:
            # There's a 'download artifact' action, but it hasn't been updated for the workflow_run action
            # (https://github.com/actions/download-artifact/issues/60) so instead we get this mess:
            - name: 📥 Download artifact
-              uses: dawidd6/action-download-artifact@246dbf436b23d7c49e21a7ab8204ca9ecd1fe615 # v2
+              uses: dawidd6/action-download-artifact@f29d1b6a8930683e80acedfbe6baa2930cd646b4 # v2
              with:
                  workflow: static_analysis.yml
                  run_id: ${{ github.event.workflow_run.id }}
@@ -22,7 +22,7 @@ jobs:
                  path: docs

            - name: 📤 Deploy to Netlify
-              uses: matrix-org/netlify-pr-preview@v2
+              uses: matrix-org/netlify-pr-preview@v3
              with:
                  path: docs
                  owner: ${{ github.event.workflow_run.head_repository.owner.login }}
@@ -32,3 +32,4 @@ jobs:
                  site_id: ${{ secrets.NETLIFY_SITE_ID }}
                  desc: Documentation preview
                  deployment_env: PR Documentation Preview
+        environment: PR Documentation Preview
@@ -1,11 +1,10 @@
 name: Build downstream artifacts
 on:
-    # We only want the Rust Crypto Cypress tests on merge queue to prevent regressions
-    # from creeping in. They take a long time to run and consume 4 concurrent runners.
-    # Anyone working on Rust Crypto is able to run the tests locally if required.
    merge_group:
        types: [checks_requested]

+    pull_request: {}
+
    # For now at least, we don't run this or the cypress-tests against pushes
    # to develop or master.
    #
@@ -21,7 +20,7 @@ concurrency:
 jobs:
    build-element-web:
        name: Build element-web
-        uses: matrix-org/matrix-react-sdk/.github/workflows/element-web.yaml@v3.79.0
+        uses: matrix-org/matrix-react-sdk/.github/workflows/element-web.yaml@v3.86.0
        with:
            matrix-js-sdk-sha: ${{ github.sha }}
            react-sdk-repository: matrix-org/matrix-react-sdk
@@ -27,7 +27,7 @@ jobs:
            pull-requests: read
        steps:
            - name: Add notice
-              uses: actions/github-script@v6
+              uses: actions/github-script@v7
              if: contains(github.event.pull_request.labels.*.name, 'X-Blocked')
              with:
                  script: |
@@ -39,7 +39,7 @@ jobs:
        if: github.event.action == 'opened'
        steps:
            - name: Check membership
-              uses: tspascoal/get-user-teams-membership@37c08f7b52a72ca95d12af2e7ab2553ca9adf13b # v2
+              uses: tspascoal/get-user-teams-membership@ba78054988f58bea69b7c6136d563236f8ed2fc0 # v3
              id: teams
              with:
                  username: ${{ github.event.pull_request.user.login }}
@@ -49,7 +49,7 @@ jobs:

            - name: Add label
              if: ${{ steps.teams.outputs.isTeamMember == 'false' }}
-              uses: actions/github-script@v6
+              uses: actions/github-script@v7
              with:
                  script: |
                      github.rest.issues.addLabels({
@@ -68,7 +68,7 @@ jobs:
            github.event.pull_request.head.repo.full_name != github.repository
        steps:
            - name: Close pull request
-              uses: actions/github-script@v6
+              uses: actions/github-script@v7
              with:
                  script: |
                      github.rest.issues.createComment({
@@ -0,0 +1,21 @@
+name: Release Drafter
+on:
+    push:
+        branches: [staging]
+    workflow_dispatch:
+        inputs:
+            previous-version:
+                description: What release to use as a base for release note purposes
+                required: false
+                type: string
+concurrency: ${{ github.workflow }}
+jobs:
+    draft:
+        runs-on: ubuntu-latest
+        steps:
+            - uses: release-drafter/release-drafter@e64b19c4c46173209ed9f2e5a2f4ca7de89a0e86 # v5
+              env:
+                  GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+              with:
+                  disable-autolabeler: true
+                  previous-version: ${{ inputs.previous-version }}
@@ -0,0 +1,85 @@
+# Gitflow merge-back master->develop
+name: Merge master -> develop
+on:
+    push:
+        branches: [master]
+    workflow_call:
+        secrets:
+            ELEMENT_BOT_TOKEN:
+                required: true
+        inputs:
+            dependencies:
+                description: List of dependencies to reset.
+                type: string
+                required: false
+concurrency: ${{ github.workflow }}
+jobs:
+    merge:
+        runs-on: ubuntu-latest
+        steps:
+            - uses: actions/checkout@v4
+              with:
+                  token: ${{ secrets.ELEMENT_BOT_TOKEN }}
+                  fetch-depth: 0
+
+            - name: Get actions scripts
+              uses: actions/checkout@v4
+              with:
+                  repository: matrix-org/matrix-js-sdk
+                  persist-credentials: false
+                  path: .action-repo
+                  sparse-checkout: |
+                      scripts/release
+
+            - uses: actions/setup-node@v4
+              with:
+                  cache: "yarn"
+
+            - name: Install Deps
+              run: "yarn install --frozen-lockfile"
+
+            - name: Set up git
+              run: |
+                  git config --global user.email "releases@riot.im"
+                  git config --global user.name "RiotRobot"
+
+            - name: Merge to develop
+              run: |
+                  git checkout develop
+                  git merge -X ours master
+
+            - name: Run post-merge-master script to revert package.json fields
+              run: ./.action-repo/scripts/release/post-merge-master.sh
+
+            - name: Reset dependencies
+              if: inputs.dependencies
+              run: |
+                  while IFS= read -r PACKAGE; do
+                      [ -z "$PACKAGE" ] && continue
+
+                      CURRENT_VERSION=$(cat package.json | jq -r .dependencies[\"$PACKAGE\"])
+                      echo "Current $PACKAGE version is $CURRENT_VERSION"
+
+                      if [ "$CURRENT_VERSION" == "null" ]
+                      then
+                          echo "Unable to find $PACKAGE in package.json"
+                          exit 1
+                      fi
+
+                      if [ "$CURRENT_VERSION" == "develop" ]
+                      then
+                          echo "Not updating dependency $PACKAGE"
+                          continue
+                      fi
+
+                      echo "Resetting $1 to develop branch..."
+                      yarn add "github:matrix-org/$PACKAGE#develop"
+                      git add -u
+                      git commit -m "Reset $PACKAGE back to develop branch"
+                  done <<< "$DEPENDENCIES"
+              env:
+                  DEPENDENCIES: ${{ inputs.dependencies }}
+                  FINAL: ${{ inputs.final }}
+
+            - name: Push changes
+              run: git push origin develop
@@ -0,0 +1,353 @@
+name: Release Make
+on:
+    workflow_call:
+        secrets:
+            ELEMENT_BOT_TOKEN:
+                required: true
+            NPM_TOKEN:
+                required: false
+            GPG_PASSPHRASE:
+                required: false
+            GPG_PRIVATE_KEY:
+                required: false
+        inputs:
+            final:
+                description: Make final release
+                required: true
+                default: false
+                type: boolean
+            npm:
+                description: Publish to npm
+                type: boolean
+                default: false
+            dependencies:
+                description: |
+                    List of dependencies to update in `npm-dep=version` format.
+                    `version` can be `"current"` to leave it at the current version.
+                type: string
+                required: false
+            include-changes:
+                description: Project to include changelog entries from in this release.
+                type: string
+                required: false
+            gpg-fingerprint:
+                description: Fingerprint of the GPG key to use for signing the git tag and assets, if any.
+                type: string
+                required: false
+            asset-path:
+                description: |
+                    The path to the asset you want to upload, if any. You can use glob patterns here.
+                    Will be GPG signed and an `.asc` file included in the release artifacts if `gpg-fingerprint` is set.
+                type: string
+                required: false
+            expected-asset-count:
+                description: The number of expected assets, including signatures, excluding generated zip & tarball.
+                type: number
+                required: false
+jobs:
+    release:
+        name: Release
+        runs-on: ubuntu-latest
+        environment: Release
+        steps:
+            - name: Load GPG key
+              id: gpg
+              if: inputs.gpg-fingerprint
+              uses: crazy-max/ghaction-import-gpg@82a020f1f7f605c65dd2449b392a52c3fcfef7ef # v6
+              with:
+                  gpg_private_key: ${{ secrets.GPG_PRIVATE_KEY }}
+                  passphrase: ${{ secrets.GPG_PASSPHRASE }}
+                  fingerprint: ${{ inputs.gpg-fingerprint }}
+
+            - name: Get draft release
+              id: release
+              uses: cardinalby/git-get-release-action@cedef2faf69cb7c55b285bad07688d04430b7ada # v1
+              env:
+                  GITHUB_TOKEN: ${{ github.token }}
+              with:
+                  draft: true
+                  latest: true
+
+            - uses: actions/checkout@v4
+              with:
+                  ref: staging
+                  token: ${{ secrets.ELEMENT_BOT_TOKEN }}
+                  fetch-depth: 0
+
+            - name: Get actions scripts
+              uses: actions/checkout@v4
+              with:
+                  repository: matrix-org/matrix-js-sdk
+                  persist-credentials: false
+                  path: .action-repo
+                  sparse-checkout: |
+                      .github/actions
+                      scripts/release
+
+            - name: Prepare variables
+              id: prepare
+              run: |
+                  echo "VERSION=$VERSION" >> $GITHUB_ENV
+                  {
+                      echo "RELEASE_NOTES<<EOF"
+                      echo "$BODY"
+                      echo "EOF"
+                  } >> $GITHUB_ENV
+
+                  HAS_DIST=0
+                  jq -e .scripts.dist package.json >/dev/null 2>&1 && HAS_DIST=1
+                  echo "has-dist-script=$HAS_DIST" >> $GITHUB_OUTPUT
+              env:
+                  BODY: ${{ steps.release.outputs.body }}
+                  VERSION: ${{ steps.release.outputs.tag_name }}
+
+            - name: Finalise version
+              if: inputs.final
+              run: echo "VERSION=$(echo $VERSION | cut -d- -f1)" >> $GITHUB_ENV
+
+            - name: Check version number not in use
+              uses: actions/github-script@v7
+              with:
+                  script: |
+                      const { VERSION } = process.env;
+                      github.rest.repos.getReleaseByTag({
+                          owner: context.repo.owner,
+                          repo: context.repo.repo,
+                          tag: VERSION,
+                      }).then(() => {
+                          core.setFailed(`Version ${VERSION} already exists`);
+                      }).catch(() => {
+                        // This is fine, we expect there to not be any release with this version yet
+                      });
+
+            - name: Set up git
+              run: |
+                  git config --global user.email "releases@riot.im"
+                  git config --global user.name "RiotRobot"
+
+            - uses: actions/setup-node@v4
+              with:
+                  cache: "yarn"
+
+            - name: Install dependencies
+              run: "yarn install --frozen-lockfile"
+
+            - name: Update dependencies
+              id: update-dependencies
+              if: inputs.dependencies
+              run: |
+                  UPDATED=()
+                  while IFS= read -r DEPENDENCY; do
+                      [ -z "$DEPENDENCY" ] && continue
+                      IFS="=" read -r PACKAGE UPDATE_VERSION <<< "$DEPENDENCY"
+
+                      CURRENT_VERSION=$(cat package.json | jq -r .dependencies[\"$PACKAGE\"])
+                      echo "Current $PACKAGE version is $CURRENT_VERSION"
+
+                      if [ "$CURRENT_VERSION" == "null" ]
+                      then
+                          echo "Unable to find $PACKAGE in package.json"
+                          exit 1
+                      fi
+
+                      if [ "$UPDATE_VERSION" == "current" ] || [ "$UPDATE_VERSION" == "$CURRENT_VERSION" ]
+                      then
+                          echo "Not updating dependency $PACKAGE"
+                          continue
+                      fi
+
+                      echo "Upgrading $PACKAGE to $UPDATE_VERSION..."
+                      yarn upgrade "$PACKAGE@$UPDATE_VERSION" --exact
+                      git add -u
+                      git commit -m "Upgrade $PACKAGE to $UPDATE_VERSION"
+                      UPDATED+=("$PACKAGE")
+                  done <<< "$DEPENDENCIES"
+
+                  JSON=$(jq --compact-output --null-input '$ARGS.positional' --args -- "${UPDATED[@]}")
+                  echo "updated=$JSON" >> $GITHUB_OUTPUT
+              env:
+                  DEPENDENCIES: ${{ inputs.dependencies }}
+
+            - name: Prevent develop dependencies
+              if: inputs.dependencies
+              run: |
+                  ret=0
+                  cat package.json | jq '.dependencies[]' | grep -q '#develop' || ret=$?
+                  if [ "$ret" -eq 0 ]; then
+                      echo "package.json contains develop dependencies. Refusing to release."
+                      exit
+                  fi
+
+            - name: Bump package.json version
+              run: yarn version --no-git-tag-version --new-version "${VERSION#v}"
+
+            - name: Ingest upstream changes
+              if: |
+                  inputs.include-changes &&
+                  (!inputs.dependencies || contains(fromJSON(steps.update-dependencies.outputs.updated), inputs.include-changes))
+              uses: actions/github-script@v7
+              env:
+                  RELEASE_ID: ${{ steps.release.outputs.id }}
+                  DEPENDENCY: ${{ inputs.include-changes }}
+              with:
+                  retries: 3
+                  script: |
+                      const { RELEASE_ID: releaseId, DEPENDENCY, VERSION } = process.env;
+                      const { owner, repo } = context.repo;
+                      const script = require("./.action-repo/scripts/release/merge-release-notes.js");
+                      const notes = await script({
+                          github,
+                          releaseId,
+                          dependencies: [DEPENDENCY.replace("$VERSION", VERSION)],
+                      });
+                      core.exportVariable("RELEASE_NOTES", notes);
+
+            - name: Add to CHANGELOG.md
+              if: inputs.final
+              run: |
+                  mv CHANGELOG.md CHANGELOG.md.old
+                  HEADER="Changes in [${VERSION#v}](https://github.com/${{ github.repository }}/releases/tag/$VERSION) ($(date '+%Y-%m-%d'))"
+
+                  {
+                      echo "$HEADER"
+                      printf '=%.0s' $(seq ${#HEADER})
+                      echo ""
+                      echo "$RELEASE_NOTES"
+                      echo ""
+                  } > CHANGELOG.md
+
+                  cat CHANGELOG.md.old >> CHANGELOG.md
+                  rm CHANGELOG.md.old
+                  git add CHANGELOG.md
+
+            - name: Run pre-release script to update package.json fields
+              run: |
+                  ./.action-repo/scripts/release/pre-release.sh
+                  git add package.json
+
+            - name: Commit changes
+              run: git commit -m "$VERSION"
+
+            - name: Build assets
+              if: steps.prepare.outputs.has-dist-script == '1'
+              run: DIST_VERSION="$VERSION" yarn dist
+
+            - name: Upload release assets & signatures
+              if: inputs.asset-path
+              uses: ./.action-repo/.github/actions/upload-release-assets
+              with:
+                  gpg-fingerprint: ${{ inputs.gpg-fingerprint }}
+                  upload-url: ${{ steps.release.outputs.upload_url }}
+                  asset-path: ${{ inputs.asset-path }}
+
+            - name: Create signed tag
+              if: inputs.gpg-fingerprint
+              run: |
+                  GIT_COMMITTER_EMAIL="$SIGNING_ID" GPG_TTY=$(tty) git tag -u "$SIGNING_ID" -m "Release $VERSION" "$VERSION"
+              env:
+                  SIGNING_ID: ${{ steps.gpg.outputs.email }}
+
+            - name: Generate & upload tarball signature
+              if: inputs.gpg-fingerprint
+              uses: ./.action-repo/.github/actions/sign-release-tarball
+              with:
+                  gpg-fingerprint: ${{ inputs.gpg-fingerprint }}
+                  upload-url: ${{ steps.release.outputs.upload_url }}
+
+            # We defer pushing changes until after the release assets are built,
+            # signed & uploaded to improve the atomicity of this action.
+            - name: Push changes to staging
+              run: |
+                  git push origin staging $TAG
+                  git reset --hard
+              env:
+                  TAG: ${{ inputs.gpg-fingerprint && env.VERSION || '' }}
+
+            - name: Validate tarball signature
+              if: inputs.gpg-fingerprint
+              run: |
+                  wget https://github.com/$GITHUB_REPOSITORY/archive/refs/tags/$VERSION.tar.gz
+                  gpg --verify "$VERSION.tar.gz.asc" "$VERSION.tar.gz"
+
+            - name: Validate release has expected assets
+              if: inputs.expected-asset-count
+              uses: actions/github-script@v7
+              env:
+                  RELEASE_ID: ${{ steps.release.outputs.id }}
+                  EXPECTED_ASSET_COUNT: ${{ inputs.expected-asset-count }}
+              with:
+                  retries: 3
+                  script: |
+                      const { RELEASE_ID: release_id, EXPECTED_ASSET_COUNT } = process.env;
+                      const { owner, repo } = context.repo;
+
+                      const { data: release } = await github.rest.repos.getRelease({
+                          owner,
+                          repo,
+                          release_id,
+                      });
+
+                      if (release.assets.length !== parseInt(EXPECTED_ASSET_COUNT, 10)) {
+                          core.setFailed(`Found ${release.assets.length} assets but expected ${EXPECTED_ASSET_COUNT}`);
+                      }
+
+            - name: Merge to master
+              if: inputs.final
+              run: |
+                  git checkout master
+                  git merge -X theirs staging
+                  git push origin master
+
+            - name: Publish release
+              uses: actions/github-script@v7
+              env:
+                  RELEASE_ID: ${{ steps.release.outputs.id }}
+                  FINAL: ${{ inputs.final }}
+              with:
+                  retries: 3
+                  github-token: ${{ secrets.ELEMENT_BOT_TOKEN }}
+                  script: |
+                      const { RELEASE_ID: release_id, RELEASE_NOTES, VERSION, FINAL } = process.env;
+                      const { owner, repo } = context.repo;
+
+                      const opts = {
+                          owner,
+                          repo,
+                          release_id,
+                          tag_name: VERSION,
+                          name: VERSION,
+                          draft: false,
+                          body: RELEASE_NOTES,
+                      };
+
+                      if (FINAL == "true") {
+                          opts.prerelease = false;
+                          opts.make_latest = true;
+                      }
+
+                      github.rest.repos.updateRelease(opts);
+
+    npm:
+        name: Publish to npm
+        needs: release
+        if: inputs.npm
+        uses: matrix-org/matrix-js-sdk/.github/workflows/release-npm.yml@develop
+        secrets:
+            NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
+
+    update-labels:
+        name: Advance release blocker labels
+        needs: release
+        runs-on: ubuntu-latest
+        steps:
+            - id: repository
+              run: echo "REPO=${GITHUB_REPOSITORY#*/}" >> $GITHUB_OUTPUT
+
+            - uses: garganshu/github-label-updater@3770d15ebfed2fe2cb06a241047bc340f774a7d1 # v1.0.0
+              with:
+                  owner: ${{ github.repository_owner }}
+                  repo: ${{ steps.repository.outputs.REPO }}
+                  token: ${{ secrets.GITHUB_TOKEN }}
+                  filter-labels: X-Upcoming-Release-Blocker
+                  remove-labels: X-Upcoming-Release-Blocker
+                  add-labels: X-Release-Blocker
@@ -1,4 +1,3 @@
-# Must only be called from `release#published` triggers
 name: Publish to npm
 on:
    workflow_call:
@@ -12,9 +11,11 @@ jobs:
        steps:
            - name: 🧮 Checkout code
              uses: actions/checkout@v4
+              with:
+                  ref: staging

            - name: 🔧 Yarn cache
-              uses: actions/setup-node@v3
+              uses: actions/setup-node@v4
              with:
                  cache: "yarn"
                  registry-url: "https://registry.npmjs.org"
@@ -24,7 +25,7 @@ jobs:

            - name: 🚀 Publish to npm
              id: npm-publish
-              uses: JS-DevTools/npm-publish@5a85faf05d2ade2d5b6682bfe5359915d5159c6c # v2.2.1
+              uses: JS-DevTools/npm-publish@4b07b26a2f6e0a51846e1870223e545bae91c552 # v3.0.1
              with:
                  token: ${{ secrets.NPM_TOKEN }}
                  access: public
@@ -32,7 +33,7 @@ jobs:
                  ignore-scripts: false

            - name: 🎖️ Add `latest` dist-tag to final releases
-              if: github.event.release.prerelease == false && steps.npm-publish.outputs.id
+              if: steps.npm-publish.outputs.id && !contains(steps.npm-publish.outputs.id, '-rc.')
              run: npm dist-tag add "$release" latest
              env:
                  NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}
@@ -1,11 +1,38 @@
 name: Release Process
 on:
-    release:
-        types: [published]
-concurrency: ${{ github.workflow }}-${{ github.ref }}
+    workflow_dispatch:
+        inputs:
+            mode:
+                description: What type of release
+                required: true
+                default: rc
+                type: choice
+                options:
+                    - rc
+                    - final
+            docs:
+                description: Publish docs
+                required: true
+                type: boolean
+                default: true
+            npm:
+                description: Publish to npm
+                required: true
+                type: boolean
+                default: true
+concurrency: ${{ github.workflow }}
 jobs:
-    jsdoc:
+    release:
+        uses: matrix-org/matrix-js-sdk/.github/workflows/release-make.yml@develop
+        secrets: inherit
+        with:
+            final: ${{ inputs.mode == 'final' }}
+            npm: ${{ inputs.npm }}
+
+    docs:
        name: Publish Documentation
+        needs: release
+        if: inputs.docs
        runs-on: ubuntu-latest
        steps:
            - name: 🧮 Checkout code
@@ -18,7 +45,7 @@ jobs:
                  path: _docs

            - name: 🔧 Yarn cache
-              uses: actions/setup-node@v3
+              uses: actions/setup-node@v4
              with:
                  cache: "yarn"

@@ -36,17 +63,14 @@ jobs:
                  yarn gendoc
                  symlinks -rc _docs

-            - name: 🚀 Deploy
+            - name: 🔨 Set up git
              run: |
                  git config --global user.email "releases@riot.im"
                  git config --global user.name "RiotRobot"
+
+            - name: 🚀 Deploy
+              run: |
                  git add . --all
                  git commit -m "Update docs"
                  git push
              working-directory: _docs
-
-    npm:
-        name: Publish
-        uses: matrix-org/matrix-js-sdk/.github/workflows/release-npm.yml@develop
-        secrets:
-            NPM_TOKEN: ${{ secrets.NPM_TOKEN }}
@@ -6,18 +6,55 @@ on:
            SONAR_TOKEN:
                required: true
        inputs:
+            sharded:
+                type: boolean
+                required: false
+                description: "Whether to combine multiple LCOV and jest-sonar-report files in coverage artifact"
            extra_args:
                type: string
                required: false
                description: "Extra args to pass to SonarCloud"
 jobs:
+    # This is a workaround for https://github.com/SonarSource/SonarJS/issues/578
+    prepare:
+        name: Prepare
+        if: |
+            github.event.workflow_run.conclusion == 'success' &&
+            github.event.workflow_run.event != 'merge_group' &&
+            inputs.sharded
+        runs-on: ubuntu-latest
+        outputs:
+            extra_args: |
+                -Dsonar.javascript.lcov.reportPaths=${{ steps.extra_args.outputs.reportPaths }}
+                -Dsonar.testExecutionReportPaths=${{ steps.extra_args.outputs.testExecutionReportPaths }}
+        steps:
+            # There's a 'download artifact' action, but it hasn't been updated for the workflow_run action
+            # (https://github.com/actions/download-artifact/issues/60) so instead we get this mess:
+            - name: 📥 Download artifact
+              uses: dawidd6/action-download-artifact@f29d1b6a8930683e80acedfbe6baa2930cd646b4 # v2
+              with:
+                  workflow: tests.yaml
+                  run_id: ${{ github.event.workflow_run.id }}
+                  name: coverage
+                  path: coverage
+
+            - id: extra_args
+              run: |
+                  coverage=$(find coverage -type f -name '*lcov.info' | tr '\n' ',' | sed 's/,$//g')
+                  echo "reportPaths=$coverage" >> $GITHUB_OUTPUT
+                  reports=$(find coverage -type f -name 'jest-sonar-report*.xml' | tr '\n' ',' | sed 's/,$//g')
+                  echo "testExecutionReportPaths=$reports" >> $GITHUB_OUTPUT
+
    sonarqube:
        runs-on: ubuntu-latest
-        if: github.event.workflow_run.conclusion == 'success'
+        needs: prepare
+        if: |
+            always() && !failure() && !cancelled() &&
+            github.event.workflow_run.conclusion == 'success'
        steps:
            # We create the status here and then update it to success/failure in the `report` stage
            # This provides an easy link to this workflow_run from the PR before Cypress is done.
-            - uses: Sibz/github-status-action@faaa4d96fecf273bd762985e0e7f9f933c774918 # v1
+            - uses: Sibz/github-status-action@071b5370da85afbb16637d6eed8524a06bc2053e # v1
              with:
                  authToken: ${{ secrets.GITHUB_TOKEN }}
                  state: pending
@@ -27,7 +64,7 @@ jobs:

            - name: "🩻 SonarCloud Scan"
              id: sonarcloud
-              uses: matrix-org/sonarcloud-workflow-action@v2.5
+              uses: matrix-org/sonarcloud-workflow-action@v2.7
              # workflow_run fails report against the develop commit always, we don't want that for PRs
              continue-on-error: ${{ github.event.workflow_run.head_branch != 'develop' }}
              with:
@@ -40,9 +77,9 @@ jobs:
                  coverage_run_id: ${{ github.event.workflow_run.id }}
                  coverage_workflow_name: tests.yml
                  coverage_extract_path: coverage
-                  extra_args: ${{ inputs.extra_args }}
+                  extra_args: ${{ inputs.extra_args }} ${{ needs.prepare.outputs.extra_args }}

-            - uses: Sibz/github-status-action@faaa4d96fecf273bd762985e0e7f9f933c774918 # v1
+            - uses: Sibz/github-status-action@071b5370da85afbb16637d6eed8524a06bc2053e # v1
              if: always()
              with:
                  authToken: ${{ secrets.GITHUB_TOKEN }}
@@ -8,38 +8,11 @@ concurrency:
    group: ${{ github.workflow }}-${{ github.event.workflow_run.head_branch }}
    cancel-in-progress: true
 jobs:
-    # This is a workaround for https://github.com/SonarSource/SonarJS/issues/578
-    prepare:
-        name: Prepare
-        if: github.event.workflow_run.conclusion == 'success' && github.event.workflow_run.event != 'merge_group'
-        runs-on: ubuntu-latest
-        outputs:
-            reportPaths: ${{ steps.extra_args.outputs.reportPaths }}
-            testExecutionReportPaths: ${{ steps.extra_args.outputs.testExecutionReportPaths }}
-        steps:
-            # There's a 'download artifact' action, but it hasn't been updated for the workflow_run action
-            # (https://github.com/actions/download-artifact/issues/60) so instead we get this mess:
-            - name: 📥 Download artifact
-              uses: dawidd6/action-download-artifact@246dbf436b23d7c49e21a7ab8204ca9ecd1fe615 # v2
-              with:
-                  workflow: tests.yaml
-                  run_id: ${{ github.event.workflow_run.id }}
-                  name: coverage
-                  path: coverage
-
-            - id: extra_args
-              run: |
-                  coverage=$(find coverage -type f -name '*lcov.info' | tr '\n' ',' | sed 's/,$//g')
-                  echo "reportPaths=$coverage" >> $GITHUB_OUTPUT
-                  reports=$(find coverage -type f -name 'jest-sonar-report*.xml' | tr '\n' ',' | sed 's/,$//g')
-                  echo "testExecutionReportPaths=$reports" >> $GITHUB_OUTPUT
-
    sonarqube:
        name: 🩻 SonarQube
        if: github.event.workflow_run.conclusion == 'success' && github.event.workflow_run.event != 'merge_group'
-        needs: prepare
        uses: matrix-org/matrix-js-sdk/.github/workflows/sonarcloud.yml@develop
        secrets:
            SONAR_TOKEN: ${{ secrets.SONAR_TOKEN }}
        with:
-            extra_args: -Dsonar.javascript.lcov.reportPaths=${{ needs.prepare.outputs.reportPaths }} -Dsonar.testExecutionReportPaths=${{ needs.prepare.outputs.testExecutionReportPaths }}
+            sharded: true
@@ -15,7 +15,7 @@ jobs:
        steps:
            - uses: actions/checkout@v4

-            - uses: actions/setup-node@v3
+            - uses: actions/setup-node@v4
              with:
                  cache: "yarn"

@@ -41,7 +41,7 @@ jobs:
        steps:
            - uses: actions/checkout@v4

-            - uses: actions/setup-node@v3
+            - uses: actions/setup-node@v4
              with:
                  cache: "yarn"

@@ -51,13 +51,29 @@ jobs:
            - name: Run Linter
              run: "yarn run lint:js"

+    workflow_lint:
+        name: "Workflow Lint"
+        runs-on: ubuntu-latest
+        steps:
+            - uses: actions/checkout@v4
+
+            - uses: actions/setup-node@v4
+              with:
+                  cache: "yarn"
+
+            - name: Install Deps
+              run: "yarn install --frozen-lockfile"
+
+            - name: Run Linter
+              run: "yarn lint:workflows"
+
    docs:
        name: "JSDoc Checker"
        runs-on: ubuntu-latest
        steps:
            - uses: actions/checkout@v4

-            - uses: actions/setup-node@v3
+            - uses: actions/setup-node@v4
              with:
                  cache: "yarn"

@@ -12,19 +12,20 @@ env:
    ENABLE_COVERAGE: ${{ github.event_name != 'merge_group' }}
 jobs:
    jest:
-        name: "Jest [${{ matrix.specs }}] (Node ${{ matrix.node }})"
+        name: "Jest [${{ matrix.specs }}] (Node ${{ matrix.node == '*' && 'latest' || matrix.node }})"
        runs-on: ubuntu-latest
        timeout-minutes: 10
        strategy:
            matrix:
-                specs: [browserify, integ, unit]
-                node: [18, latest]
+                specs: [integ, unit]
+                node: [18, "lts/*", 21]
        steps:
            - name: Checkout code
              uses: actions/checkout@v4

            - name: Setup Node
-              uses: actions/setup-node@v3
+              id: setupNode
+              uses: actions/setup-node@v4
              with:
                  cache: "yarn"
                  node-version: ${{ matrix.node }}
@@ -32,13 +33,9 @@ jobs:
            - name: Install dependencies
              run: "yarn install"

-            - name: Build
-              if: matrix.specs == 'browserify'
-              run: "yarn build"
-
            - name: Get number of CPU cores
              id: cpu-cores
-              uses: SimenB/github-actions-cpu-cores@410541432439795d30db6501fb1d8178eb41e502 # v1
+              uses: SimenB/github-actions-cpu-cores@97ba232459a8e02ff6121db9362b09661c875ab8 # v2

            - name: Run tests
              run: |
@@ -55,7 +52,7 @@ jobs:

            - name: Move coverage files into place
              if: env.ENABLE_COVERAGE == 'true'
-              run: mv coverage/lcov.info coverage/${{ matrix.node }}-${{ matrix.specs }}.lcov.info
+              run: mv coverage/lcov.info coverage/${{ steps.setupNode.outputs.node-version }}-${{ matrix.specs }}.lcov.info

            - name: Upload Artifact
              if: env.ENABLE_COVERAGE == 'true'
@@ -85,7 +82,7 @@ jobs:
        steps:
            - name: Skip SonarCloud on merge queues
              if: env.ENABLE_COVERAGE == 'false'
-              uses: Sibz/github-status-action@faaa4d96fecf273bd762985e0e7f9f933c774918 # v1
+              uses: Sibz/github-status-action@071b5370da85afbb16637d6eed8524a06bc2053e # v1
              with:
                  authToken: ${{ secrets.GITHUB_TOKEN }}
                  state: success
@@ -0,0 +1,11 @@
+name: Move labelled issues to correct projects
+
+on:
+    issues:
+        types: [labeled]
+
+jobs:
+    call-triage-labelled:
+        uses: vector-im/element-web/.github/workflows/triage-labelled.yml@develop
+        secrets:
+            ELEMENT_BOT_TOKEN: ${{ secrets.ELEMENT_BOT_TOKEN }}
@@ -1,38 +0,0 @@
-name: Upgrade Dependencies
-on:
-    workflow_dispatch: {}
-    workflow_call:
-        secrets:
-            ELEMENT_BOT_TOKEN:
-                required: true
-jobs:
-    upgrade:
-        runs-on: ubuntu-latest
-        steps:
-            - uses: actions/checkout@v4
-
-            - uses: actions/setup-node@v3
-              with:
-                  cache: "yarn"
-
-            - name: Upgrade
-              run: yarn upgrade && yarn install
-
-            - name: Create Pull Request
-              id: cpr
-              uses: peter-evans/create-pull-request@153407881ec5c347639a548ade7d8ad1d6740e38 # v5
-              with:
-                  token: ${{ secrets.ELEMENT_BOT_TOKEN }}
-                  branch: actions/upgrade-deps
-                  delete-branch: true
-                  title: Upgrade dependencies
-                  labels: |
-                      Dependencies
-                      T-Task
-
-            - name: Enable automerge
-              run: gh pr merge --merge --auto "$PR_NUMBER"
-              if: steps.cpr.outputs.pull-request-operation == 'created'
-              env:
-                  GH_TOKEN: ${{ secrets.ELEMENT_BOT_TOKEN }}
-                  PR_NUMBER: ${{ steps.cpr.outputs.pull-request-number }}
@@ -0,0 +1,4 @@
+#!/usr/bin/env sh
+. "$(dirname "$0")/_/husky.sh"
+
+npx lint-staged
@@ -0,0 +1,4 @@
+{
+    "*.(ts|tsx)": ["eslint --fix", "prettier --write"],
+    "*.(py|md|yaml)": ["prettier --write"]
+}
@@ -1,5 +1,136 @@
-Changes in [28.2.0-rc.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v28.2.0-rc.1) (2023-09-19)
-============================================================================================================
+Changes in [31.1.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v31.1.0) (2024-01-19)
+==================================================================================================
+## ✨ Features
+
+* Broaden spec version support ([#4016](https://github.com/matrix-org/matrix-js-sdk/pull/4016)). Contributed by @RiotRobot.
+
+
+Changes in [31.0.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v31.0.0) (2024-01-16)
+==================================================================================================
+## 🚨 BREAKING CHANGES
+
+* Bump minimum spec version to v1.5 ([#3970](https://github.com/matrix-org/matrix-js-sdk/pull/3970)). Contributed by @richvdh.
+
+## ✨ Features
+
+* Bump minimum spec version to v1.5 ([#3970](https://github.com/matrix-org/matrix-js-sdk/pull/3970)). Contributed by @richvdh.
+* Send authenticated /versions request ([#3968](https://github.com/matrix-org/matrix-js-sdk/pull/3968)). Contributed by @dbkr.
+
+## 🐛 Bug Fixes
+
+* Revert "Bump matrix-sdk-crypto-wasm to 3.6.0" ([#3991](https://github.com/matrix-org/matrix-js-sdk/pull/3991)). Contributed by @andybalaam.
+* #22606 Fix "Remove" button  to users without "m.room.redaction" ([#3981](https://github.com/matrix-org/matrix-js-sdk/pull/3981)). Contributed by @rashmitpankhania.
+* ElementR: Ensure Encryption order per room ([#3973](https://github.com/matrix-org/matrix-js-sdk/pull/3973)). Contributed by @BillCarsonFr.
+* Element-R: fix `bootstrapSecretStorage` not resetting key backup when requested ([#3976](https://github.com/matrix-org/matrix-js-sdk/pull/3976)). Contributed by @uhoreg.
+
+
+Changes in [30.3.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v30.3.0) (2023-12-19)
+==================================================================================================
+## ✨ Features
+
+* Element-R: disable sending room key requests ([#3939](https://github.com/matrix-org/matrix-js-sdk/pull/3939)). Contributed by @richvdh.
+
+## 🐛 Bug Fixes
+
+* Fix notifications appearing for old events ([#3946](https://github.com/matrix-org/matrix-js-sdk/pull/3946)). Contributed by @dbkr.
+* Don't back up keys that we got from backup ([#3934](https://github.com/matrix-org/matrix-js-sdk/pull/3934)). Contributed by @uhoreg.
+* Fix upload with empty Content-Type ([#3918](https://github.com/matrix-org/matrix-js-sdk/pull/3918)). Contributed by @JakubOnderka.
+* Prevent phantom notifications from events not in a room's timeline ([#3942](https://github.com/matrix-org/matrix-js-sdk/pull/3942)). Contributed by @dbkr.
+
+
+Changes in [30.2.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v30.2.0) (2023-12-05)
+==================================================================================================
+## ✨ Features
+
+* Only await key query after lazy members resolved ([#3902](https://github.com/matrix-org/matrix-js-sdk/pull/3902)). Contributed by @BillCarsonFr.
+
+## 🐛 Bug Fixes
+
+* Rewrite receipt-handling code ([#3901](https://github.com/matrix-org/matrix-js-sdk/pull/3901)). Contributed by @andybalaam.
+* Explicitly free some Rust-side objects ([#3911](https://github.com/matrix-org/matrix-js-sdk/pull/3911)). Contributed by @richvdh.
+* Fix type for TimestampToEventResponse.origin\_server\_ts ([#3906](https://github.com/matrix-org/matrix-js-sdk/pull/3906)). Contributed by @Half-Shot.
+
+
+Changes in [30.1.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v30.1.0) (2023-11-21)
+==================================================================================================
+## ✨ Features
+
+* Rotate per-participant keys when a member leaves ([#3833](https://github.com/matrix-org/matrix-js-sdk/pull/3833)). Contributed by @dbkr.
+* Add E2EE for embedded mode of Element Call ([#3667](https://github.com/matrix-org/matrix-js-sdk/pull/3667)). Contributed by @SimonBrandner.
+
+## 🐛 Bug Fixes
+
+* Shorten TimelineWindow when an event is removed ([#3862](https://github.com/matrix-org/matrix-js-sdk/pull/3862)). Contributed by @andybalaam.
+* Ignore receipts pointing at missing or invalid events ([#3817](https://github.com/matrix-org/matrix-js-sdk/pull/3817)). Contributed by @andybalaam.
+* Fix members being loaded from server on initial sync (defeating lazy loading) ([#3830](https://github.com/matrix-org/matrix-js-sdk/pull/3830)). Contributed by @BillCarsonFr.
+
+
+Changes in [30.0.1](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v30.0.1) (2023-11-13)
+==================================================================================================
+
+## 🐛 Bug Fixes
+ * Ensure `setUserCreator` is called when a store is assigned ([\#3867](https://github.com/matrix-org/matrix-js-sdk/pull/3867)). Fixes vector-im/element-web#26520. Contributed by @MidhunSureshR.
+
+Changes in [30.0.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v30.0.0) (2023-11-07)
+==================================================================================================
+
+## 🚨 BREAKING CHANGES
+ * Refactor & make base64 functions browser-safe ([\#3818](https://github.com/matrix-org/matrix-js-sdk/pull/3818)).
+
+## 🦖 Deprecations
+ * Deprecate `MatrixEvent.toJSON` ([\#3801](https://github.com/matrix-org/matrix-js-sdk/pull/3801)).
+
+## ✨ Features
+ * Element-R: Add the git sha of the binding crate to `CryptoApi#getVersion` ([\#3838](https://github.com/matrix-org/matrix-js-sdk/pull/3838)). Contributed by @florianduros.
+ * Element-R: Wire up `globalBlacklistUnverifiedDevices` field to rust crypto encryption settings ([\#3790](https://github.com/matrix-org/matrix-js-sdk/pull/3790)). Fixes vector-im/element-web#26315. Contributed by @florianduros.
+ * Element-R: Wire up room rotation ([\#3807](https://github.com/matrix-org/matrix-js-sdk/pull/3807)). Fixes vector-im/element-web#26318. Contributed by @florianduros.
+ * Element-R: Add current version of the rust-sdk and vodozemac ([\#3825](https://github.com/matrix-org/matrix-js-sdk/pull/3825)). Contributed by @florianduros.
+ * Element-R: Wire up room history visibility ([\#3805](https://github.com/matrix-org/matrix-js-sdk/pull/3805)). Fixes vector-im/element-web#26319. Contributed by @florianduros.
+ * Element-R: log when we send to-device messages ([\#3810](https://github.com/matrix-org/matrix-js-sdk/pull/3810)).
+
+## 🐛 Bug Fixes
+ * Fix reemitter not being correctly wired on user objects created in storage classes ([\#3796](https://github.com/matrix-org/matrix-js-sdk/pull/3796)). Contributed by @MidhunSureshR.
+ * Element-R: silence log errors when viewing a pending event ([\#3824](https://github.com/matrix-org/matrix-js-sdk/pull/3824)).
+ * Don't emit a closed event if the indexeddb is closed by Element ([\#3832](https://github.com/matrix-org/matrix-js-sdk/pull/3832)). Fixes vector-im/element-web#25941. Contributed by @dhenneke.
+ * Element-R: silence log errors when viewing a decryption failure ([\#3821](https://github.com/matrix-org/matrix-js-sdk/pull/3821)).
+
+Changes in [29.1.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v29.1.0) (2023-10-24)
+==================================================================================================
+
+## ✨ Features
+ * OIDC: refresh tokens ([\#3764](https://github.com/matrix-org/matrix-js-sdk/pull/3764)). Contributed by @kerryarchibald.
+ * OIDC: add `prompt` param to auth url creation ([\#3794](https://github.com/matrix-org/matrix-js-sdk/pull/3794)). Contributed by @kerryarchibald.
+ * Allow applications to specify their own logger instance ([\#3792](https://github.com/matrix-org/matrix-js-sdk/pull/3792)). Fixes #1899.
+ * Export AutoDiscoveryError and fix type of ALL_ERRORS ([\#3768](https://github.com/matrix-org/matrix-js-sdk/pull/3768)).
+
+## 🐛 Bug Fixes
+ * Fix sending call member events on leave ([\#3799](https://github.com/matrix-org/matrix-js-sdk/pull/3799)). Fixes vector-im/element-call#1763.
+ * Don't use event.sender in CallMembership ([\#3793](https://github.com/matrix-org/matrix-js-sdk/pull/3793)).
+ * Element-R: Don't mark QR code verification as done until it's done ([\#3791](https://github.com/matrix-org/matrix-js-sdk/pull/3791)). Fixes vector-im/element-web#26293.
+ * Element-R: Connect device to key backup when crypto is created ([\#3784](https://github.com/matrix-org/matrix-js-sdk/pull/3784)). Fixes vector-im/element-web#26316. Contributed by @florianduros.
+ * Element-R: Avoid errors in `VerificationRequest.generateQRCode` when QR code is unavailable ([\#3779](https://github.com/matrix-org/matrix-js-sdk/pull/3779)). Fixes vector-im/element-web#26300. Contributed by @florianduros.
+ * ElementR: Check key backup when user identity changes ([\#3760](https://github.com/matrix-org/matrix-js-sdk/pull/3760)). Fixes vector-im/element-web#26244. Contributed by @florianduros.
+ * Element-R: emit `VerificationRequestReceived` on incoming request ([\#3762](https://github.com/matrix-org/matrix-js-sdk/pull/3762)). Fixes vector-im/element-web#26245.
+
+Changes in [29.0.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v29.0.0) (2023-10-10)
+==================================================================================================
+
+## 🚨 BREAKING CHANGES
+ * Remove browserify builds ([\#3759](https://github.com/matrix-org/matrix-js-sdk/pull/3759)).
+
+## ✨ Features
+ * Export AutoDiscoveryError and fix type of ALL_ERRORS ([\#3768](https://github.com/matrix-org/matrix-js-sdk/pull/3768)).
+ * Support for stable MSC3882 get_login_token ([\#3416](https://github.com/matrix-org/matrix-js-sdk/pull/3416)). Contributed by @hughns.
+ * Remove IsUserMention and IsRoomMention from DEFAULT_OVERRIDE_RULES ([\#3752](https://github.com/matrix-org/matrix-js-sdk/pull/3752)). Contributed by @kerryarchibald.
+
+## 🐛 Bug Fixes
+ * Fix a case where joinRoom creates a duplicate Room object ([\#3747](https://github.com/matrix-org/matrix-js-sdk/pull/3747)).
+ * Add membershipID to call memberships ([\#3745](https://github.com/matrix-org/matrix-js-sdk/pull/3745)).
+ * Fix the warning for messages from unsigned devices ([\#3743](https://github.com/matrix-org/matrix-js-sdk/pull/3743)).
+ * Stop keep alive, when sync was stoped ([\#3720](https://github.com/matrix-org/matrix-js-sdk/pull/3720)). Contributed by @finsterwalder.
+
+Changes in [28.2.0](https://github.com/matrix-org/matrix-js-sdk/releases/tag/v28.2.0) (2023-09-26)
+==================================================================================================

 ## 🦖 Deprecations
 * Implement `getEncryptionInfoForEvent` and deprecate `getEventEncryptionInfo` ([\#3693](https://github.com/matrix-org/matrix-js-sdk/pull/3693)).
@@ -23,19 +23,7 @@ endpoints from before Matrix 1.1, for example.

 ## In a browser

-### Note, the browserify build has been deprecated. Please use a bundler like webpack or vite instead.
-
-Download the browser version from
-https://github.com/matrix-org/matrix-js-sdk/releases/latest and add that as a
-`<script>` to your page. There will be a global variable `matrixcs`
-attached to `window` through which you can access the SDK. See below for how to
-include libolm to enable end-to-end-encryption.
-
-The browser bundle supports recent versions of browsers. Typically this is ES2015
-or `> 0.5%, last 2 versions, Firefox ESR, not dead` if using
-[browserlists](https://github.com/browserslist/browserslist).
-
-Please check [the working browser example](examples/browser) for more information.
+### Note, the browserify build has been removed. Please use a bundler like webpack or vite instead.

 ## In Node.js

@@ -70,7 +58,7 @@ await client.startClient({ initialSyncLimit: 10 });
 You can perform a call to `/sync` to get the current state of the client:

 ```javascript
-client.once("sync", function (state, prevState, res) {
+client.once(ClientEvent.sync, function (state, prevState, res) {
    if (state === "PREPARED") {
        console.log("prepared");
    } else {
@@ -95,7 +83,7 @@ client.sendEvent("roomId", "m.room.message", content, "", (err, res) => {
 To listen for message events:

 ```javascript
-client.on("Room.timeline", function (event, room, toStartOfTimeline) {
+client.on(RoomEvent.Timeline, function (event, room, toStartOfTimeline) {
    if (event.getType() !== "m.room.message") {
        return; // only use messages
    }
@@ -156,12 +144,12 @@ are updated.

 ```javascript
 // Listen for low-level MatrixEvents
-client.on("event", function (event) {
+client.on(ClientEvent.Event, function (event) {
    console.log(event.getType());
 });

 // Listen for typing changes
-client.on("RoomMember.typing", function (event, member) {
+client.on(RoomMemberEvent.Typing, function (event, member) {
    if (member.typing) {
        console.log(member.name + " is typing...");
    } else {
@@ -223,7 +211,7 @@ const matrixClient = sdk.createClient({
 ### Automatically join rooms when invited

 ```javascript
-matrixClient.on("RoomMember.membership", function (event, member) {
+matrixClient.on(RoomMemberEvent.Membership, function (event, member) {
    if (member.membership === "invite" && member.userId === myUserId) {
        matrixClient.joinRoom(member.roomId).then(function () {
            console.log("Auto-joined %s", member.roomId);
@@ -237,7 +225,7 @@ matrixClient.startClient();
 ### Print out messages for all rooms

 ```javascript
-matrixClient.on("Room.timeline", function (event, room, toStartOfTimeline) {
+matrixClient.on(RoomEvent.Timeline, function (event, room, toStartOfTimeline) {
    if (toStartOfTimeline) {
        return; // don't print paginated results
    }
@@ -269,7 +257,7 @@ Output:
 ### Print out membership lists whenever they are changed

 ```javascript
-matrixClient.on("RoomState.members", function (event, state, member) {
+matrixClient.on(RoomStateEvent.Members, function (event, state, member) {
    const room = matrixClient.getRoom(state.roomId);
    if (!room) {
        return;
@@ -363,7 +351,7 @@ First, you need to pull in the right build tools:

 ## Building

-To build a browser version from scratch when developing::
+To build a browser version from scratch when developing:

 ```
 $ yarn build
@@ -375,9 +363,6 @@ To run tests (Jest):
 $ yarn test
 ```

-> **Note**
-> The `sync-browserify.spec.ts` requires a browser build (`yarn build`) in order to pass
-
 To run linting:

 ```
@@ -0,0 +1,9 @@
+# Summary
+
+-   [Introduction](../README.md)
+
+# Deep dive
+
+-   [Release Process](release.md)
+-   [Storage notes](storage-notes.md)
+-   [Unverified devices](warning-on-unverified-devices.md)
@@ -0,0 +1,24 @@
+# Release Process
+
+## Hotfix and off-cycle releases
+
+1. Prepare the `staging` branch by using the backport automation and manually merging
+2. Go to [Releasing](#Releasing)
+
+## Release candidates
+
+1. Prepare the `staging` branch by running the [branch cut automation](https://github.com/vector-im/element-web/actions/workflows/release_prepare.yml)
+2. Go to [Releasing](#Releasing)
+
+## Releasing
+
+1. Open the [Releases page](https://github.com/matrix-org/matrix-js-sdk/releases) and inspect the draft release there
+2. Make any modifications to the release notes and tag/version as required
+3. Run [workflow](https://github.com/matrix-org/matrix-js-sdk/actions/workflows/release.yml) with the type set appropriately
+
+## Artifacts
+
+Releasing the Matrix JS SDK has just two artifacts:
+
+-   Package published to [npm](https://github.com/matrix-org/matrix-js-sdk)
+-   Docs published to [Github Pages](https://matrix-org.github.io/matrix-js-sdk/)
@@ -1,31 +1,29 @@
 Random notes from Matthew on the two possible approaches for warning users about unexpected
 unverified devices popping up in their rooms....

-Original idea...
-================
+# Original idea...

 Warn when an existing user adds an unknown device to a room.

 Warn when a user joins the room with unverified or unknown devices.

 Warn when you initial sync if the room has any unverified devices in it.
- ^ this is good enough if we're doing local storage.
- OR, better:
+^ this is good enough if we're doing local storage.
+OR, better:
 Warn when you initial sync if the room has any new undefined devices since you were last there.
- => This means persisting the rooms that devices are in, across initial syncs.
+=> This means persisting the rooms that devices are in, across initial syncs.

-
-Updated idea...
-===============
+# Updated idea...

 Warn when the user tries to send a message:
-  - If the room has unverified devices which the user has not yet been told about in the context of this room
-    ...or in the context of this user?  currently all verification is per-user, not per-room.
+
+-   If the room has unverified devices which the user has not yet been told about in the context of this room
+    ...or in the context of this user? currently all verification is per-user, not per-room.
    ...this should be good enough.

-  - so track whether we have warned the user or not about unverified devices - blocked, unverified, verified, unverified_warned.
+-   so track whether we have warned the user or not about unverified devices - blocked, unverified, verified, unverified_warned.
    throw an error when trying to encrypt if there are pure unverified devices there
    app will have to search for the devices which are pure unverified to warn about them - have to do this from MembersList anyway?
-      - or megolm could warn which devices are causing the problems.
+    -   or megolm could warn which devices are causing the problems.

-Why do we wait to establish outbound sessions?  It just makes a horrible pause when we first try to send a message... but could otherwise unnecessarily consume resources?
+Why do we wait to establish outbound sessions? It just makes a horrible pause when we first try to send a message... but could otherwise unnecessarily consume resources?
@@ -1,10 +0,0 @@
-To try it out, **you must build the SDK first** and then host this folder:
-
-```
- $ yarn install
- $ yarn build
- $ cd examples/browser
- $ python -m http.server 8003
-```
-
-Then visit `http://localhost:8003`.
@@ -1,9 +0,0 @@
-console.log("Loading browser sdk");
-
-var client = matrixcs.createClient({ baseUrl: "https://matrix.org" });
-client.publicRooms().then(function (data) {
-    console.log("data %s [...]", JSON.stringify(data).substring(0, 100));
-    console.log("Congratulations! The SDK is working on the browser!");
-    var result = document.getElementById("result");
-    result.innerHTML = "<p>The SDK appears to be working correctly.</p>";
-});
@@ -1,17 +0,0 @@
-<html lang="en">
-    <head>
-        <title>Test</title>
-        <meta charset="utf-8" />
-        <link rel="icon" href="data:," />
-        <script src="lib/matrix.js"></script>
-        <script src="browserTest.js"></script>
-    </head>
-    <body>
-        Sanity Testing (check the console) : This example is here to make sure that the SDK works inside a browser. It
-        simply does a GET /publicRooms on matrix.org
-        <br />
-        You should see a message confirming that the SDK works below:
-        <br />
-        <div id="result"></div>
-    </body>
-</html>
@@ -1 +0,0 @@
-../../../dist/browser-matrix.js
@@ -1,2 +0,0 @@
-olm.js
-olm.wasm
@@ -1 +0,0 @@
-../../../dist/browser-matrix.js
@@ -1,60 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-    <head>
-        <meta charset="UTF-8" />
-        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-        <meta http-equiv="X-UA-Compatible" content="ie=edge" />
-        <title>Test Crypto in Browser</title>
-        <script src="lib/olm.js"></script>
-        <script src="lib/matrix.js"></script>
-    </head>
-    <body>
-        <h1>Testing export/import of Olm devices in the browser</h1>
-        <ul>
-            <li>Make sure you built the current version of the Matrix JS SDK (<code>yarn build</code>)</li>
-            <li>
-                copy <code>olm.js</code> and <code>olm.wasm</code> from a recent release of Olm (was tested with version
-                3.1.4) in directory <code>lib/</code>
-            </li>
-            <li>start a local Matrix homeserver (on port 8008, or change the port in the code)</li>
-            <li>Serve this HTML file (e.g. <code>python3 -m http.server</code>) and go to it through your browser</li>
-            <li>
-                in the JS console, do:
-                <pre>
-aliceMatrixClient = await newMatrixClient("alice-"+randomHex());
-await aliceMatrixClient.exportDevice();
-await aliceMatrixClient.getAccessToken();
-            </pre
-                >
-            </li>
-            <li>
-                copy the result of <code>exportDevice</code> and <code>getAccessToken</code> somewhere (<strong
-                    >not</strong
-                >
-                in a JS variable as it will be destroyed when you refresh the page)
-            </li>
-            <li><strong>refresh the page (F5)</strong> to make sure the client is destroyed</li>
-            <li>
-                Do the following, replacing <code>ALICE_ID</code>
-                with the user ID of Alice (you can find it in the exported data)
-                <pre>
-bobMatrixClient = await newMatrixClient("bob-"+randomHex());
-roomId = await bobMatrixClient.createEncryptedRoom([ALICE_ID]);
-await bobMatrixClient.sendTextMessage('Hi Alice!', roomId);
-            </pre
-                >
-            </li>
-            <li>Again, <strong>refresh the page (F5)</strong>. You may want to clear your console as well.</li>
-            <li>
-                Now do the following, using the exported data and the access token you saved previously:
-                <pre>
-aliceMatrixClient = await importMatrixClient(EXPORTED_DATA, ACCESS_TOKEN);
-            </pre
-                >
-            </li>
-            <li>You should see the message sent by Bob printed in the console.</li>
-        </ul>
-
-        <script src="olm-device-export-import.js"></script>
-    </body>
-</html>
@@ -1,105 +0,0 @@
-if (!Olm) {
-    console.error("global.Olm does not seem to be present." + " Did you forget to add olm in the lib/ directory?");
-}
-
-const BASE_URL = "http://localhost:8008";
-const ROOM_CRYPTO_CONFIG = { algorithm: "m.megolm.v1.aes-sha2" };
-const PASSWORD = "password";
-
-// useful to create new usernames
-window.randomHex = () => Math.floor(Math.random() * 10 ** 6).toString(16);
-
-window.newMatrixClient = async function (username) {
-    const registrationClient = matrixcs.createClient(BASE_URL);
-
-    const userRegisterResult = await registrationClient.register(username, PASSWORD, null, { type: "m.login.dummy" });
-
-    const matrixClient = matrixcs.createClient({
-        baseUrl: BASE_URL,
-        userId: userRegisterResult.user_id,
-        accessToken: userRegisterResult.access_token,
-        deviceId: userRegisterResult.device_id,
-        sessionStore: new matrixcs.WebStorageSessionStore(window.localStorage),
-        cryptoStore: new matrixcs.MemoryCryptoStore(),
-    });
-
-    extendMatrixClient(matrixClient);
-
-    await matrixClient.initCrypto();
-    await matrixClient.startClient();
-    return matrixClient;
-};
-
-window.importMatrixClient = async function (exportedDevice, accessToken) {
-    const matrixClient = matrixcs.createClient({
-        baseUrl: BASE_URL,
-        deviceToImport: exportedDevice,
-        accessToken,
-        sessionStore: new matrixcs.WebStorageSessionStore(window.localStorage),
-        cryptoStore: new matrixcs.MemoryCryptoStore(),
-    });
-
-    extendMatrixClient(matrixClient);
-
-    await matrixClient.initCrypto();
-    await matrixClient.startClient();
-    return matrixClient;
-};
-
-function extendMatrixClient(matrixClient) {
-    // automatic join
-    matrixClient.on("RoomMember.membership", async (event, member) => {
-        if (member.membership === "invite" && member.userId === matrixClient.getUserId()) {
-            await matrixClient.joinRoom(member.roomId);
-            // setting up of room encryption seems to be triggered automatically
-            // but if we don't wait for it the first messages we send are unencrypted
-            await matrixClient.setRoomEncryption(member.roomId, { algorithm: "m.megolm.v1.aes-sha2" });
-        }
-    });
-
-    matrixClient.onDecryptedMessage = (message) => {
-        console.log("Got encrypted message: ", message);
-    };
-
-    matrixClient.on("Event.decrypted", (event) => {
-        if (event.getType() === "m.room.message") {
-            matrixClient.onDecryptedMessage(event.getContent().body);
-        } else {
-            console.log("decrypted an event of type", event.getType());
-            console.log(event);
-        }
-    });
-
-    matrixClient.createEncryptedRoom = async function (usersToInvite) {
-        const { room_id: roomId } = await this.createRoom({
-            visibility: "private",
-            invite: usersToInvite,
-        });
-
-        // matrixClient.setRoomEncryption() only updates local state
-        // but does not send anything to the server
-        // (see https://github.com/matrix-org/matrix-js-sdk/issues/905)
-        // so we do it ourselves with 'sendStateEvent'
-        await this.sendStateEvent(roomId, "m.room.encryption", ROOM_CRYPTO_CONFIG);
-        await this.setRoomEncryption(roomId, ROOM_CRYPTO_CONFIG);
-
-        // Marking all devices as verified
-        let room = this.getRoom(roomId);
-        let members = (await room.getEncryptionTargetMembers()).map((x) => x["userId"]);
-        let memberkeys = await this.downloadKeys(members);
-        for (const userId in memberkeys) {
-            for (const deviceId in memberkeys[userId]) {
-                await this.setDeviceVerified(userId, deviceId);
-            }
-        }
-
-        return roomId;
-    };
-
-    matrixClient.sendTextMessage = async function (message, roomId) {
-        return matrixClient.sendMessage(roomId, {
-            body: message,
-            msgtype: "m.text",
-        });
-    };
-}
@@ -1,6 +1,6 @@
 {
    "name": "matrix-js-sdk",
-    "version": "28.2.0-rc.1",
+    "version": "31.1.0",
    "description": "Matrix Client-Server SDK for Javascript",
    "engines": {
        "node": ">=18.0.0"
@@ -8,19 +8,17 @@
    "scripts": {
        "prepublishOnly": "yarn build",
        "start": "echo THIS IS FOR LEGACY PURPOSES ONLY. && babel src -w -s -d lib --verbose --extensions \".ts,.js\"",
-        "dist": "echo 'This is for the release script so it can make assets (browser bundle).' && yarn build",
-        "clean": "rimraf lib dist",
-        "build": "yarn build:dev && yarn build:compile-browser && yarn build:minify-browser",
+        "clean": "rimraf lib",
+        "build": "yarn build:dev",
        "build:dev": "yarn clean && git rev-parse HEAD > git-revision.txt && yarn build:compile && yarn build:types",
        "build:types": "tsc -p tsconfig-build.json --emitDeclarationOnly",
        "build:compile": "babel -d lib --verbose --extensions \".ts,.js\" src",
-        "build:compile-browser": "mkdir dist && BROWSERIFYSWAP_ENV='no-rust-crypto' browserify -d src/browser-index.ts -p [ tsify -p ./tsconfig-build.json ] | exorcist dist/browser-matrix.js.map > dist/browser-matrix.js",
-        "build:minify-browser": "terser dist/browser-matrix.js --compress --mangle --source-map --output dist/browser-matrix.min.js",
        "gendoc": "typedoc",
-        "lint": "yarn lint:types && yarn lint:js",
+        "lint": "yarn lint:types && yarn lint:js && yarn lint:workflows",
        "lint:js": "eslint --max-warnings 0 src spec && prettier --check .",
-        "lint:js-fix": "prettier --loglevel=warn --write . && eslint --fix src spec",
+        "lint:js-fix": "prettier --log-level=warn --write . && eslint --fix src spec",
        "lint:types": "tsc --noEmit",
+        "lint:workflows": "find .github/workflows -type f \\( -iname '*.yaml' -o -iname '*.yml' \\) | xargs -I {} sh -c 'echo \"Linting {}\"; action-validator \"{}\"'",
        "test": "jest",
        "test:watch": "jest --watch",
        "coverage": "yarn test --coverage"
@@ -42,7 +40,6 @@
    "author": "matrix.org",
    "license": "Apache-2.0",
    "files": [
-        "dist",
        "lib",
        "src",
        "git-revision.txt",
@@ -55,7 +52,7 @@
    ],
    "dependencies": {
        "@babel/runtime": "^7.12.5",
-        "@matrix-org/matrix-sdk-crypto-wasm": "^1.2.3-alpha.0",
+        "@matrix-org/matrix-sdk-crypto-wasm": "^3.5.0",
        "another-json": "^0.2.0",
        "bs58": "^5.0.0",
        "content-type": "^1.0.4",
@@ -70,6 +67,8 @@
        "uuid": "9"
    },
    "devDependencies": {
+        "@action-validator/cli": "^0.5.3",
+        "@action-validator/core": "^0.5.3",
        "@babel/cli": "^7.12.10",
        "@babel/core": "^7.12.10",
        "@babel/eslint-parser": "^7.12.10",
@@ -82,8 +81,8 @@
        "@babel/preset-env": "^7.12.11",
        "@babel/preset-typescript": "^7.12.7",
        "@babel/register": "^7.12.10",
-        "@casualbot/jest-sonar-reporter": "^2.2.5",
-        "@matrix-org/olm": "https://gitlab.matrix.org/api/v4/projects/27/packages/npm/@matrix-org/olm/-/@matrix-org/olm-3.2.14.tgz",
+        "@casualbot/jest-sonar-reporter": "2.2.7",
+        "@matrix-org/olm": "3.2.15",
        "@types/bs58": "^4.0.1",
        "@types/content-type": "^1.1.5",
        "@types/debug": "^4.1.7",
@@ -92,16 +91,13 @@
        "@types/node": "18",
        "@types/sdp-transform": "^2.4.5",
        "@types/uuid": "9",
-        "@typescript-eslint/eslint-plugin": "^5.45.0",
-        "@typescript-eslint/parser": "^5.45.0",
+        "@typescript-eslint/eslint-plugin": "^6.0.0",
+        "@typescript-eslint/parser": "^6.0.0",
        "allchange": "^1.0.6",
        "babel-jest": "^29.0.0",
-        "babelify": "^10.0.0",
-        "browserify": "^17.0.0",
-        "browserify-swap": "^0.2.2",
        "debug": "^4.3.4",
        "domexception": "^4.0.0",
-        "eslint": "8.48.0",
+        "eslint": "8.55.0",
        "eslint-config-google": "^0.14.0",
        "eslint-config-prettier": "^9.0.0",
        "eslint-import-resolver-typescript": "^3.5.1",
@@ -110,20 +106,20 @@
        "eslint-plugin-jsdoc": "^46.0.0",
        "eslint-plugin-matrix-org": "^1.0.0",
        "eslint-plugin-tsdoc": "^0.2.17",
-        "eslint-plugin-unicorn": "^48.0.0",
-        "exorcist": "^2.0.0",
-        "fake-indexeddb": "^4.0.0",
+        "eslint-plugin-unicorn": "^49.0.0",
+        "fake-indexeddb": "^5.0.2",
+        "fetch-mock": "9.11.0",
        "fetch-mock-jest": "^1.5.1",
+        "husky": "^8.0.3",
        "jest": "^29.0.0",
        "jest-environment-jsdom": "^29.0.0",
        "jest-localstorage-mock": "^2.4.6",
        "jest-mock": "^29.0.0",
+        "lint-staged": "^15.0.2",
        "matrix-mock-request": "^2.5.0",
-        "prettier": "2.8.8",
+        "prettier": "3.1.1",
        "rimraf": "^5.0.0",
-        "terser": "^5.5.1",
        "ts-node": "^10.9.1",
-        "tsify": "^5.0.2",
        "typedoc": "^0.24.0",
        "typedoc-plugin-coverage": "^2.1.0",
        "typedoc-plugin-mdn-links": "^3.0.3",
@@ -137,25 +133,5 @@
        "outputName": "jest-sonar-report.xml",
        "relativePaths": true
    },
-    "browserify": {
-        "transform": [
-            "browserify-swap",
-            [
-                "babelify",
-                {
-                    "sourceMaps": "inline",
-                    "presets": [
-                        "@babel/preset-env",
-                        "@babel/preset-typescript"
-                    ]
-                }
-            ]
-        ]
-    },
-    "browserify-swap": {
-        "no-rust-crypto": {
-            "src/rust-crypto/index.ts$": "./src/rust-crypto/browserify-index.ts"
-        }
-    },
    "typings": "./lib/index.d.ts"
 }
@@ -10,28 +10,6 @@ set -e
 jq --version > /dev/null || (echo "jq is required: please install it"; kill $$)

 if [ "$(git branch -lr | grep origin/develop -c)" -ge 1 ]; then
-    # When merging to develop, we need revert the `main` and `typings` fields if we adjusted them previously.
-    for i in main typings browser
-    do
-        # If a `lib` prefixed value is present, it means we adjusted the field
-        # earlier at publish time, so we should revert it now.
-        if [ "$(jq -r ".matrix_lib_$i" package.json)" != "null" ]; then
-            # If there's a `src` prefixed value, use that, otherwise delete.
-            # This is used to delete the `typings` field and reset `main` back
-            # to the TypeScript source.
-            src_value=$(jq -r ".matrix_src_$i" package.json)
-            if [ "$src_value" != "null" ]; then
-                jq ".$i = .matrix_src_$i" package.json > package.json.new && mv package.json.new package.json && yarn prettier --write package.json
-            else
-                jq "del(.$i)" package.json > package.json.new && mv package.json.new package.json && yarn prettier --write package.json
-            fi
-        fi
-    done
-
-    if [ -n "$(git ls-files --modified package.json)" ]; then
-        echo "Committing develop package.json"
-        git commit package.json -m "Resetting package fields for development"
-    fi
-
+    "$(dirname "$0")/scripts/release/post-merge-master.sh"
    git push origin develop
 fi
@@ -175,18 +175,7 @@ echo "yarn version"
 # manually commit the result.
 yarn version --no-git-tag-version --new-version "$release"

-# For the published and dist versions of the package, we copy the
-# `matrix_lib_main` and `matrix_lib_typings` fields to `main` and `typings` (if
-# they exist). This small bit of gymnastics allows us to use the TypeScript
-# source directly for development without needing to build before linting or
-# testing.
-for i in main typings browser
-do
-    lib_value=$(jq -r ".matrix_lib_$i" package.json)
-    if [ "$lib_value" != "null" ]; then
-        jq ".$i = .matrix_lib_$i" package.json > package.json.new && mv package.json.new package.json && yarn prettier --write package.json
-    fi
-done
+"$(dirname "$0")/scripts/release/pre-release.sh"

 # commit yarn.lock if it exists, is versioned, and is modified
 if [[ -f yarn.lock && $(git status --porcelain yarn.lock | grep '^ M') ]];
@@ -0,0 +1,104 @@
+#!/usr/bin/env node
+
+const fs = require("fs");
+
+async function getRelease(github, dependency) {
+    let owner;
+    let repo;
+    let tag;
+    if (dependency.includes("/") && dependency.includes("@")) {
+        owner = dependency.split("/")[0];
+        repo = dependency.split("/")[1].split("@")[0];
+        tag = dependency.split("@")[1];
+    } else {
+        const upstreamPackageJson = JSON.parse(fs.readFileSync(`./node_modules/${dependency}/package.json`, "utf8"));
+        [owner, repo] = upstreamPackageJson.repository.url.split("/").slice(-2);
+        tag = `v${upstreamPackageJson.version}`;
+    }
+
+    const response = await github.rest.repos.getReleaseByTag({
+        owner,
+        repo,
+        tag,
+    });
+    return response.data;
+}
+
+const HEADING_PREFIX = "## ";
+
+const main = async ({ github, releaseId, dependencies }) => {
+    const { GITHUB_REPOSITORY } = process.env;
+    const [owner, repo] = GITHUB_REPOSITORY.split("/");
+
+    const sections = new Map();
+    let heading = null;
+    for (const dependency of dependencies) {
+        const release = await getRelease(github, dependency);
+        for (const line of release.body.split("\n")) {
+            if (line.startsWith(HEADING_PREFIX)) {
+                heading = line.trim();
+                sections.set(heading, []);
+                continue;
+            }
+            if (heading && line) {
+                sections.get(heading).push(line.trim());
+            }
+        }
+    }
+
+    const { data: release } = await github.rest.repos.getRelease({
+        owner,
+        repo,
+        release_id: releaseId,
+    });
+
+    const headings = ["🚨 BREAKING CHANGES", "🦖 Deprecations", "✨ Features", "🐛 Bug Fixes", "🧰 Maintenance"].map(
+        (h) => HEADING_PREFIX + h,
+    );
+
+    heading = null;
+    const output = [];
+    for (const line of [...release.body.split("\n"), null]) {
+        if (line === null || line.startsWith(HEADING_PREFIX)) {
+            // If we have a heading, and it's not the first in the list of pending headings, output the section.
+            // If we're processing the last line (null) then output all remaining sections.
+            while (headings.length > 0 && (line === null || (heading && headings[0] !== heading))) {
+                const heading = headings.shift();
+                if (sections.has(heading)) {
+                    output.push(heading);
+                    output.push(...sections.get(heading));
+                }
+            }
+
+            if (heading && sections.has(heading)) {
+                const lastIsBlank = !output.at(-1)?.trim();
+                if (lastIsBlank) output.pop();
+                output.push(...sections.get(heading));
+                if (lastIsBlank) output.push("");
+            }
+            heading = line;
+        }
+        output.push(line);
+    }
+
+    return output.join("\n");
+};
+
+// This is just for testing locally
+// Needs environment variables GITHUB_TOKEN & GITHUB_REPOSITORY
+if (require.main === module) {
+    const { Octokit } = require("@octokit/rest");
+    const github = new Octokit({ auth: process.env.GITHUB_TOKEN });
+    if (process.argv.length < 4) {
+        // eslint-disable-next-line no-console
+        console.error("Usage: node merge-release-notes.js owner/repo:release_id npm-package-name ...");
+        process.exit(1);
+    }
+    const [releaseId, ...dependencies] = process.argv.slice(2);
+    main({ github, releaseId, dependencies }).then((output) => {
+        // eslint-disable-next-line no-console
+        console.log(output);
+    });
+}
+
+module.exports = main;
@@ -0,0 +1,22 @@
+#!/bin/bash
+
+# When merging to develop, we need revert the `main` and `typings` fields if we adjusted them previously.
+for i in main typings browser
+do
+    # If a `lib` prefixed value is present, it means we adjusted the field earlier at publish time, so we should revert it now.
+    if [ "$(jq -r ".matrix_lib_$i" package.json)" != "null" ]; then
+        # If there's a `src` prefixed value, use that, otherwise delete.
+        # This is used to delete the `typings` field and reset `main` back to the TypeScript source.
+        src_value=$(jq -r ".matrix_src_$i" package.json)
+        if [ "$src_value" != "null" ]; then
+            jq ".$i = .matrix_src_$i" package.json > package.json.new && mv package.json.new package.json && yarn prettier --write package.json
+        else
+            jq "del(.$i)" package.json > package.json.new && mv package.json.new package.json && yarn prettier --write package.json
+        fi
+    fi
+done
+
+if [ -n "$(git ls-files --modified package.json)" ]; then
+    echo "Committing develop package.json"
+    git commit package.json -m "Resetting package fields for development"
+fi
@@ -0,0 +1,14 @@
+#!/bin/bash
+
+# For the published and dist versions of the package,
+# we copy the `matrix_lib_main` and `matrix_lib_typings` fields to `main` and `typings` (if they exist).
+# This small bit of gymnastics allows us to use the TypeScript source directly for development without
+# needing to build before linting or testing.
+
+for i in main typings browser
+do
+    lib_value=$(jq -r ".matrix_lib_$i" package.json)
+    if [ "$lib_value" != "null" ]; then
+        jq ".$i = .matrix_lib_$i" package.json > package.json.new && mv package.json.new package.json && yarn prettier --write package.json
+    fi
+done
@@ -1,34 +0,0 @@
-/*
-Copyright 2020 The Matrix.org Foundation C.I.C.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-import "../../dist/browser-matrix"; // uses browser-matrix instead of the src
-import type { default as BrowserMatrix } from "../../src/browser-index";
-
-// stub for browser-matrix browserify tests
-// @ts-ignore
-global.XMLHttpRequest = jest.fn();
-
-afterAll(() => {
-    // clean up XMLHttpRequest mock
-    // @ts-ignore
-    global.XMLHttpRequest = undefined;
-});
-
-// Akin to spec/setupTests.ts - but that won't affect the browser-matrix bundle
-global.matrixcs = {
-    ...global.matrixcs,
-    timeoutSignal: () => new AbortController().signal,
-} as typeof BrowserMatrix;
@@ -1,92 +0,0 @@
-/*
-Copyright 2020 The Matrix.org Foundation C.I.C.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-import HttpBackend from "matrix-mock-request";
-
-import "./setupTests"; // uses browser-matrix instead of the src
-import type { MatrixClient } from "../../src";
-
-const USER_ID = "@user:test.server";
-const DEVICE_ID = "device_id";
-const ACCESS_TOKEN = "access_token";
-const ROOM_ID = "!room_id:server.test";
-
-describe("Browserify Test", function () {
-    let client: MatrixClient;
-    let httpBackend: HttpBackend;
-
-    beforeEach(() => {
-        httpBackend = new HttpBackend();
-        client = new global.matrixcs.MatrixClient({
-            baseUrl: "http://test.server",
-            userId: USER_ID,
-            accessToken: ACCESS_TOKEN,
-            deviceId: DEVICE_ID,
-            fetchFn: httpBackend.fetchFn as typeof global.fetch,
-        });
-
-        httpBackend.when("GET", "/versions").respond(200, {});
-        httpBackend.when("GET", "/pushrules").respond(200, {});
-        httpBackend.when("POST", "/filter").respond(200, { filter_id: "fid" });
-    });
-
-    afterEach(async () => {
-        client.stopClient();
-        client.http.abort();
-        httpBackend.verifyNoOutstandingRequests();
-        httpBackend.verifyNoOutstandingExpectation();
-        await httpBackend.stop();
-    });
-
-    it("Sync", async () => {
-        const event = {
-            type: "m.room.member",
-            room_id: ROOM_ID,
-            content: {
-                membership: "join",
-                name: "Displayname",
-            },
-            event_id: "$foobar",
-        };
-
-        const syncData = {
-            next_batch: "batch1",
-            rooms: {
-                join: {
-                    [ROOM_ID]: {
-                        timeline: {
-                            events: [event],
-                            limited: false,
-                        },
-                    },
-                },
-            },
-        };
-
-        httpBackend.when("GET", "/sync").respond(200, syncData);
-        httpBackend.when("GET", "/sync").respond(200, syncData);
-
-        const syncPromise = new Promise((r) => client.once(global.matrixcs.ClientEvent.Sync, r));
-        const unexpectedErrorFn = jest.fn();
-        client.once(global.matrixcs.ClientEvent.SyncUnexpectedError, unexpectedErrorFn);
-
-        client.startClient();
-
-        await httpBackend.flushAllExpected();
-        await syncPromise;
-        expect(unexpectedErrorFn).not.toHaveBeenCalled();
-    }, 20000); // additional timeout as this test can take quite a while
-});
@@ -31,9 +31,12 @@ import {
    SELF_CROSS_SIGNING_PRIVATE_KEY_BASE64,
    SELF_CROSS_SIGNING_PUBLIC_KEY_BASE64,
    SIGNED_CROSS_SIGNING_KEYS_DATA,
+    SIGNED_TEST_DEVICE_DATA,
    USER_CROSS_SIGNING_PRIVATE_KEY_BASE64,
 } from "../../test-utils/test-data";
+import * as testData from "../../test-utils/test-data";
 import { E2EKeyResponder } from "../../test-utils/E2EKeyResponder";
+import { AccountDataAccumulator } from "../../test-utils/AccountDataAccumulator";

 afterEach(() => {
    // reset fake-indexeddb after each test, to make sure we don't leak connections
@@ -97,6 +100,12 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("cross-signing (%s)", (backend: s
        /** an object which intercepts `/keys/upload` requests on the test homeserver */
        new E2EKeyReceiver(homeserverUrl);

+        // Silence warnings from the backup manager
+        fetchMock.getOnce(new URL("/_matrix/client/v3/room_keys/version", homeserverUrl).toString(), {
+            status: 404,
+            body: { errcode: "M_NOT_FOUND" },
+        });
+
        await initCrypto(aliceClient);
    });

@@ -236,6 +245,53 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("cross-signing (%s)", (backend: s
                `[${TEST_USER_ID}].[${TEST_DEVICE_ID}].signatures.[${TEST_USER_ID}].[ed25519:${SELF_CROSS_SIGNING_PUBLIC_KEY_BASE64}]`,
            );
        });
+
+        it("can bootstrapCrossSigning twice", async () => {
+            mockSetupCrossSigningRequests();
+
+            const authDict = { type: "test" };
+            await bootstrapCrossSigning(authDict);
+
+            // a second call should do nothing except GET requests
+            fetchMock.mockClear();
+            await bootstrapCrossSigning(authDict);
+            const calls = fetchMock.calls((url, opts) => opts.method != "GET");
+            expect(calls.length).toEqual(0);
+        });
+
+        newBackendOnly("will upload existing cross-signing keys to an established secret storage", async () => {
+            // This rather obscure codepath covers the case that:
+            //   - 4S is set up and working
+            //   - our device has private cross-signing keys, but has not published them to 4S
+            //
+            // To arrange that, we call `bootstrapCrossSigning` on our main device, and then (pretend to) set up 4S from
+            // a *different* device. Then, when we call `bootstrapCrossSigning` again, it should do the honours.
+
+            mockSetupCrossSigningRequests();
+            const accountDataAccumulator = new AccountDataAccumulator();
+            accountDataAccumulator.interceptGetAccountData();
+
+            const authDict = { type: "test" };
+            await bootstrapCrossSigning(authDict);
+
+            // Pretend that another device has uploaded a 4S key
+            accountDataAccumulator.accountDataEvents.set("m.secret_storage.default_key", { key: "key_id" });
+            accountDataAccumulator.accountDataEvents.set("m.secret_storage.key.key_id", {
+                key: "keykeykey",
+                algorithm: SECRET_STORAGE_ALGORITHM_V1_AES,
+            });
+
+            // Prepare for the cross-signing keys
+            const p = accountDataAccumulator.interceptSetAccountData(":type(m.cross_signing..*)");
+
+            await bootstrapCrossSigning(authDict);
+            await p;
+
+            // The cross-signing keys should have been uploaded
+            expect(accountDataAccumulator.accountDataEvents.has("m.cross_signing.master")).toBeTruthy();
+            expect(accountDataAccumulator.accountDataEvents.has("m.cross_signing.self_signing")).toBeTruthy();
+            expect(accountDataAccumulator.accountDataEvents.has("m.cross_signing.user_signing")).toBeTruthy();
+        });
    });

    describe("getCrossSigningStatus()", () => {
@@ -339,4 +395,48 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("cross-signing (%s)", (backend: s
            expect(userSigningKeyId).toBe(getPubKey(crossSigningKeys.user_signing_key));
        });
    });
+
+    describe("crossSignDevice", () => {
+        beforeEach(async () => {
+            jest.useFakeTimers();
+
+            // make sure that there is another device which we can sign
+            e2eKeyResponder.addDeviceKeys(SIGNED_TEST_DEVICE_DATA);
+
+            // Complete initialsync, to get the outgoing requests going
+            mockInitialApiRequests(aliceClient.getHomeserverUrl());
+            syncResponder.sendOrQueueSyncResponse({ next_batch: 1 });
+            await aliceClient.startClient();
+            await syncPromise(aliceClient);
+
+            // Wait for legacy crypto to find the device
+            await jest.advanceTimersByTimeAsync(10);
+
+            const devices = await aliceClient.getCrypto()!.getUserDeviceInfo([aliceClient.getSafeUserId()]);
+            expect(devices.get(aliceClient.getSafeUserId())!.has(testData.TEST_DEVICE_ID)).toBeTruthy();
+        });
+
+        afterEach(async () => {
+            jest.useRealTimers();
+        });
+
+        it("fails for an unknown device", async () => {
+            await expect(aliceClient.getCrypto()!.crossSignDevice("unknown")).rejects.toThrow("Unknown device");
+        });
+
+        it("cross-signs the device", async () => {
+            mockSetupCrossSigningRequests();
+            await aliceClient.getCrypto()!.bootstrapCrossSigning({});
+
+            fetchMock.mockClear();
+            await aliceClient.getCrypto()!.crossSignDevice(testData.TEST_DEVICE_ID);
+
+            // check that a sig for the device was uploaded
+            const calls = fetchMock.calls("upload-sigs");
+            expect(calls.length).toEqual(1);
+            const body = JSON.parse(calls[0][1]!.body as string);
+            const deviceSig = body[aliceClient.getSafeUserId()][testData.TEST_DEVICE_ID];
+            expect(deviceSig).toHaveProperty("signatures");
+        });
+    });
 });
@@ -18,15 +18,23 @@ import fetchMock from "fetch-mock-jest";
 import "fake-indexeddb/auto";
 import { IDBFactory } from "fake-indexeddb";

-import { createClient, CryptoEvent, ICreateClientOpts, MatrixClient, TypedEventEmitter } from "../../../src";
+import { createClient, CryptoEvent, ICreateClientOpts, IEvent, MatrixClient, TypedEventEmitter } from "../../../src";
 import { SyncResponder } from "../../test-utils/SyncResponder";
 import { E2EKeyReceiver } from "../../test-utils/E2EKeyReceiver";
 import { E2EKeyResponder } from "../../test-utils/E2EKeyResponder";
 import { mockInitialApiRequests } from "../../test-utils/mockEndpoints";
-import { awaitDecryption, CRYPTO_BACKENDS, InitCrypto, syncPromise } from "../../test-utils/test-utils";
+import {
+    advanceTimersUntil,
+    awaitDecryption,
+    CRYPTO_BACKENDS,
+    InitCrypto,
+    syncPromise,
+} from "../../test-utils/test-utils";
 import * as testData from "../../test-utils/test-data";
 import { KeyBackupInfo } from "../../../src/crypto-api/keybackup";
 import { IKeyBackup } from "../../../src/crypto/backup";
+import { flushPromises } from "../../test-utils/flushPromises";
+import { defer, IDeferred } from "../../../src/utils";

 const ROOM_ID = testData.TEST_ROOM_ID;

@@ -110,9 +118,9 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backe
    /** an object which intercepts `/keys/query` requests on the test homeserver */
    let e2eKeyResponder: E2EKeyResponder;

-    jest.useFakeTimers();
-
    beforeEach(async () => {
+        jest.useFakeTimers();
+
        // anything that we don't have a specific matcher for silently returns a 404
        fetchMock.catch(404);
        fetchMock.config.warnOnFallback = false;
@@ -134,6 +142,7 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backe
        await jest.runAllTimersAsync();

        fetchMock.mockReset();
+        jest.restoreAllMocks();
    });

    async function initTestClient(opts: Partial<ICreateClientOpts> = {}): Promise<MatrixClient> {
@@ -149,48 +158,131 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backe
        return client;
    }

-    it("Alice checks key backups when receiving a message she can't decrypt", async function () {
-        const syncResponse = {
+    describe("Key backup check on UTD message", () => {
+        // sync response which contains an encrypted event
+        const SYNC_RESPONSE = {
            next_batch: 1,
-            rooms: {
-                join: {
-                    [ROOM_ID]: {
-                        timeline: {
-                            events: [testData.ENCRYPTED_EVENT],
-                        },
-                    },
-                },
-            },
+            rooms: { join: { [ROOM_ID]: { timeline: { events: [testData.ENCRYPTED_EVENT] } } } },
        };

-        fetchMock.get(
-            "express:/_matrix/client/v3/room_keys/keys/:room_id/:session_id",
-            testData.CURVE25519_KEY_BACKUP_DATA,
-        );
-        fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);
+        const EXPECTED_URL =
+            [
+                "https://alice-server.com/_matrix/client/v3/room_keys/keys",
+                encodeURIComponent(testData.TEST_ROOM_ID),
+                encodeURIComponent(testData.MEGOLM_SESSION_DATA.session_id),
+            ].join("/") + "?version=1";

-        aliceClient = await initTestClient();
-        const aliceCrypto = aliceClient.getCrypto()!;
-        await aliceCrypto.storeSessionBackupPrivateKey(Buffer.from(testData.BACKUP_DECRYPTION_KEY_BASE64, "base64"));
+        /** Flush promises enough times to get the crypto stacks to make the backup request */
+        async function flushBackupRequest() {
+            // we have to run flushPromises lots of times. It seems like each time the rust code touches indexeddb,
+            // it needs another round of flushPromises to progress, or something.
+            for (let i = 0; i < 10; i++) {
+                await flushPromises();
+            }
+        }

-        // start after saving the private key
-        await aliceClient.startClient();
+        beforeEach(async () => {
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);

-        // tell Alice to trust the dummy device that signed the backup, and re-check the backup.
-        // XXX: should we automatically re-check after a device becomes verified?
-        await waitForDeviceList();
-        await aliceCrypto.setDeviceVerified(testData.TEST_USER_ID, testData.TEST_DEVICE_ID);
-        await aliceClient.getCrypto()!.checkKeyBackupAndEnable();
+            // ignore requests to send room key requests
+            fetchMock.put("express:/_matrix/client/v3/sendToDevice/m.room_key_request/:request_id", {});

-        // Now, send Alice a message that she won't be able to decrypt, and check that she fetches the key from the backup.
-        syncResponder.sendOrQueueSyncResponse(syncResponse);
-        await syncPromise(aliceClient);
+            aliceClient = await initTestClient();
+            const aliceCrypto = aliceClient.getCrypto()!;
+            await aliceCrypto.storeSessionBackupPrivateKey(
+                Buffer.from(testData.BACKUP_DECRYPTION_KEY_BASE64, "base64"),
+                testData.SIGNED_BACKUP_DATA.version!,
+            );

-        const room = aliceClient.getRoom(ROOM_ID)!;
-        const event = room.getLiveTimeline().getEvents()[0];
-        await awaitDecryption(event, { waitOnDecryptionFailure: true });
+            // start after saving the private key
+            await aliceClient.startClient();

-        expect(event.getContent()).toEqual(testData.CLEAR_EVENT.content);
+            // tell Alice to trust the dummy device that signed the backup, and re-check the backup.
+            // XXX: should we automatically re-check after a device becomes verified?
+            await waitForDeviceList();
+            await aliceClient.getCrypto()!.setDeviceVerified(testData.TEST_USER_ID, testData.TEST_DEVICE_ID);
+            await aliceClient.getCrypto()!.checkKeyBackupAndEnable();
+        });
+
+        it("Alice checks key backups when receiving a message she can't decrypt", async () => {
+            fetchMock.get("express:/_matrix/client/v3/room_keys/keys/:room_id/:session_id", (url, request) => {
+                // check that the version is correct
+                const version = new URLSearchParams(new URL(url).search).get("version");
+                if (version == "1") {
+                    return testData.CURVE25519_KEY_BACKUP_DATA;
+                } else {
+                    return {
+                        status: 403,
+                        body: {
+                            current_version: "1",
+                            errcode: "M_WRONG_ROOM_KEYS_VERSION",
+                            error: "Wrong backup version.",
+                        },
+                    };
+                }
+            });
+
+            // Send Alice a message that she won't be able to decrypt, and check that she fetches the key from the backup.
+            syncResponder.sendOrQueueSyncResponse(SYNC_RESPONSE);
+            await syncPromise(aliceClient);
+
+            const room = aliceClient.getRoom(ROOM_ID)!;
+            const event = room.getLiveTimeline().getEvents()[0];
+            await advanceTimersUntil(awaitDecryption(event, { waitOnDecryptionFailure: true }));
+
+            expect(event.getContent()).toEqual(testData.CLEAR_EVENT.content);
+        });
+
+        it("handles error on backup query gracefully", async () => {
+            jest.spyOn(console, "error").mockImplementation(() => {});
+
+            fetchMock.get(
+                "express:/_matrix/client/v3/room_keys/keys/:room_id/:session_id",
+                { status: 404, body: { errcode: "M_NOT_FOUND" } },
+                { name: "getKey" },
+            );
+
+            // Send Alice a message that she won't be able to decrypt
+            syncResponder.sendOrQueueSyncResponse(SYNC_RESPONSE);
+            await flushBackupRequest();
+
+            const calls = fetchMock.calls("getKey");
+            expect(calls.length).toEqual(1);
+            expect(calls[0][0]).toEqual(EXPECTED_URL);
+
+            await flushBackupRequest();
+
+            // we should not have logged an error.
+            // eslint-disable-next-line no-console
+            expect(console.error).not.toHaveBeenCalled();
+        });
+
+        it("Only queries once", async () => {
+            fetchMock.get(
+                "express:/_matrix/client/v3/room_keys/keys/:room_id/:session_id",
+                { status: 404, body: { errcode: "M_NOT_FOUND" } },
+                { name: "getKey" },
+            );
+
+            // Send Alice a message that she won't be able to decrypt
+            syncResponder.sendOrQueueSyncResponse(SYNC_RESPONSE);
+            await flushBackupRequest();
+            const calls = fetchMock.calls("getKey");
+            expect(calls.length).toEqual(1);
+            expect(calls[0][0]).toEqual(EXPECTED_URL);
+
+            fetchMock.resetHistory();
+
+            // another message
+            const event2 = { ...testData.ENCRYPTED_EVENT, event_id: "$event2" };
+            const syncResponse2 = {
+                next_batch: 1,
+                rooms: { join: { [ROOM_ID]: { timeline: { events: [event2] } } } },
+            };
+            syncResponder.sendOrQueueSyncResponse(syncResponse2);
+            await flushBackupRequest();
+            expect(fetchMock.calls("getKey").length).toEqual(0);
+        });
    });

    describe("recover from backup", () => {
@@ -224,19 +316,28 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backe
                onKeyCached = resolve;
            });

-            const result = await aliceClient.restoreKeyBackupWithRecoveryKey(
-                testData.BACKUP_DECRYPTION_KEY_BASE58,
-                undefined,
-                undefined,
-                check!.backupInfo!,
-                {
-                    cacheCompleteCallback: () => onKeyCached(),
-                },
+            const result = await advanceTimersUntil(
+                aliceClient.restoreKeyBackupWithRecoveryKey(
+                    testData.BACKUP_DECRYPTION_KEY_BASE58,
+                    undefined,
+                    undefined,
+                    check!.backupInfo!,
+                    {
+                        cacheCompleteCallback: () => onKeyCached(),
+                    },
+                ),
            );

            expect(result.imported).toStrictEqual(1);

            await awaitKeyCached;
+
+            // The key should be now cached
+            const afterCache = await advanceTimersUntil(
+                aliceClient.restoreKeyBackupWithCache(undefined, undefined, check!.backupInfo!),
+            );
+
+            expect(afterCache.imported).toStrictEqual(1);
        });

        it("recover specific session from backup", async function () {
@@ -257,11 +358,13 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backe

            const check = await aliceCrypto.checkKeyBackupAndEnable();

-            const result = await aliceClient.restoreKeyBackupWithRecoveryKey(
-                testData.BACKUP_DECRYPTION_KEY_BASE58,
-                ROOM_ID,
-                testData.MEGOLM_SESSION_DATA.session_id,
-                check!.backupInfo!,
+            const result = await advanceTimersUntil(
+                aliceClient.restoreKeyBackupWithRecoveryKey(
+                    testData.BACKUP_DECRYPTION_KEY_BASE58,
+                    ROOM_ID,
+                    testData.MEGOLM_SESSION_DATA.session_id,
+                    check!.backupInfo!,
+                ),
            );

            expect(result.imported).toStrictEqual(1);
@@ -640,6 +743,7 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backe
            await aliceClient.startClient();
            await aliceCrypto.storeSessionBackupPrivateKey(
                Buffer.from(testData.BACKUP_DECRYPTION_KEY_BASE64, "base64"),
+                testData.SIGNED_BACKUP_DATA.version!,
            );

            const result = await aliceCrypto.isKeyBackupTrusted(testData.SIGNED_BACKUP_DATA);
@@ -653,6 +757,7 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backe
            await aliceClient.startClient();
            await aliceCrypto.storeSessionBackupPrivateKey(
                Buffer.from(testData.BACKUP_DECRYPTION_KEY_BASE64, "base64"),
+                testData.SIGNED_BACKUP_DATA.version!,
            );

            const backup: KeyBackupInfo = JSON.parse(JSON.stringify(testData.SIGNED_BACKUP_DATA));
@@ -784,6 +889,146 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("megolm-keys backup (%s)", (backe
        });
    });

+    describe("Backup Changed from other sessions", () => {
+        beforeEach(async () => {
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);
+
+            // ignore requests to send room key requests
+            fetchMock.put("express:/_matrix/client/v3/sendToDevice/m.room_key_request/:request_id", {});
+
+            aliceClient = await initTestClient();
+            const aliceCrypto = aliceClient.getCrypto()!;
+            await aliceCrypto.storeSessionBackupPrivateKey(
+                Buffer.from(testData.BACKUP_DECRYPTION_KEY_BASE64, "base64"),
+                testData.SIGNED_BACKUP_DATA.version!,
+            );
+
+            // start after saving the private key
+            await aliceClient.startClient();
+
+            // tell Alice to trust the dummy device that signed the backup, and re-check the backup.
+            // XXX: should we automatically re-check after a device becomes verified?
+            await waitForDeviceList();
+            await aliceClient.getCrypto()!.setDeviceVerified(testData.TEST_USER_ID, testData.TEST_DEVICE_ID);
+            await aliceClient.getCrypto()!.checkKeyBackupAndEnable();
+        });
+
+        // let aliceClient: MatrixClient;
+
+        const SYNC_RESPONSE = {
+            next_batch: 1,
+            rooms: { join: { [ROOM_ID]: { timeline: { events: [testData.ENCRYPTED_EVENT] } } } },
+        };
+
+        it("If current backup has changed, the manager should switch to the new one on UTD", async () => {
+            // =====
+            // First ensure that the client checks for keys using the backup version 1
+            /// =====
+
+            fetchMock.get(
+                "express:/_matrix/client/v3/room_keys/keys/:room_id/:session_id",
+                (url, request) => {
+                    // check that the version is correct
+                    const version = new URLSearchParams(new URL(url).search).get("version");
+                    if (version == "1") {
+                        return testData.CURVE25519_KEY_BACKUP_DATA;
+                    } else {
+                        return {
+                            status: 403,
+                            body: {
+                                current_version: "1",
+                                errcode: "M_WRONG_ROOM_KEYS_VERSION",
+                                error: "Wrong backup version.",
+                            },
+                        };
+                    }
+                },
+                { overwriteRoutes: true },
+            );
+
+            // Send Alice a message that she won't be able to decrypt, and check that she fetches the key from the backup.
+            syncResponder.sendOrQueueSyncResponse(SYNC_RESPONSE);
+            await syncPromise(aliceClient);
+
+            const room = aliceClient.getRoom(ROOM_ID)!;
+            const event = room.getLiveTimeline().getEvents()[0];
+            await advanceTimersUntil(awaitDecryption(event, { waitOnDecryptionFailure: true }));
+
+            expect(event.getContent()).toEqual(testData.CLEAR_EVENT.content);
+
+            // =====
+            // Second suppose now that the backup has changed to version 2
+            /// =====
+
+            const newBackup = {
+                ...testData.SIGNED_BACKUP_DATA,
+                version: "2",
+            };
+
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", newBackup, { overwriteRoutes: true });
+            // suppose the new key is now known
+            const aliceCrypto = aliceClient.getCrypto()!;
+            await aliceCrypto.storeSessionBackupPrivateKey(
+                Buffer.from(testData.BACKUP_DECRYPTION_KEY_BASE64, "base64"),
+                newBackup.version,
+            );
+
+            // A check backup should happen at some point
+            await aliceCrypto.checkKeyBackupAndEnable();
+
+            const awaitHasQueriedNewBackup: IDeferred<void> = defer<void>();
+
+            fetchMock.get(
+                "express:/_matrix/client/v3/room_keys/keys/:room_id/:session_id",
+                (url, request) => {
+                    // check that the version is correct
+                    const version = new URLSearchParams(new URL(url).search).get("version");
+                    if (version == newBackup.version) {
+                        awaitHasQueriedNewBackup.resolve();
+                        return testData.CURVE25519_KEY_BACKUP_DATA;
+                    } else {
+                        // awaitHasQueriedOldBackup.resolve();
+                        return {
+                            status: 403,
+                            body: {
+                                current_version: "2",
+                                errcode: "M_WRONG_ROOM_KEYS_VERSION",
+                                error: "Wrong backup version.",
+                            },
+                        };
+                    }
+                },
+                { overwriteRoutes: true },
+            );
+
+            // Send Alice a message that she won't be able to decrypt, and check that she fetches the key from the new backup.
+            const newMessage: Partial<IEvent> = {
+                type: "m.room.encrypted",
+                room_id: "!room:id",
+                sender: "@alice:localhost",
+                content: {
+                    algorithm: "m.megolm.v1.aes-sha2",
+                    ciphertext:
+                        "AwgAEpABKvf9FqPW52zeHfeVTn90a3jlBLlx7g6VDEkc2089RQUJoWpSJRiK13E83rN41wgGFJccyfoCr7ZDGJeuGYMGETTrgnLQhLs6JmyPf37JYkzxW8uS8rGUKEqTFQriKhibHVLvVacOlSIObUiKU/V3r176XuixqZF/4eyK9A22JNpInbgI10ZUT6LnApH9LR3FpZbE2zImf1uNPuvp7r0xQbW7CcJjqpH+qTPBD5zFdFnMkc2SnbXCsIOaX11Dm0krWfQz7iA26ZnI1nyZnyh7XPrCnJCRsuQH",
+                    device_id: "WVMJGTSSVB",
+                    sender_key: "E5RiY/YCIrHWaF4u416CqvblC6udK2jt9SJ/h1QeLS0",
+                    session_id: "ybnW+LGdUhoS4fHm1DAEphukO3sZ1GCqZD7UQz7L+GA",
+                },
+                event_id: "$event2",
+                origin_server_ts: 1507753887000,
+            };
+
+            const nextSyncResponse = {
+                next_batch: 2,
+                rooms: { join: { [ROOM_ID]: { timeline: { events: [newMessage] } } } },
+            };
+            syncResponder.sendOrQueueSyncResponse(nextSyncResponse);
+            await syncPromise(aliceClient);
+
+            await awaitHasQueriedNewBackup.promise;
+        });
+    });
+
    /** make sure that the client knows about the dummy device */
    async function waitForDeviceList(): Promise<void> {
        // Completing the initial sync will make the device list download outdated device lists (of which our own
@@ -0,0 +1,408 @@
+/*
+Copyright 2016-2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import Olm from "@matrix-org/olm";
+import anotherjson from "another-json";
+
+import { IContent, IDeviceKeys, IDownloadKeyResult, IEvent, Keys, MatrixClient, SigningKeys } from "../../../src";
+import { IE2EKeyReceiver } from "../../test-utils/E2EKeyReceiver";
+import { ISyncResponder } from "../../test-utils/SyncResponder";
+import { syncPromise } from "../../test-utils/test-utils";
+import { KeyBackupInfo } from "../../../src/crypto-api";
+
+/**
+ * @module
+ *
+ * A set of utilities for creating Olm accounts and sessions, and encrypting/decrypting with Olm/Megolm.
+ */
+
+/** Create an Olm Account object */
+export async function createOlmAccount(): Promise<Olm.Account> {
+    await Olm.init();
+    const testOlmAccount = new Olm.Account();
+    testOlmAccount.create();
+    return testOlmAccount;
+}
+
+/**
+ * Get the device keys for the test Olm Account
+ *
+ * @param olmAccount - Test olm account
+ * @param userId - The user ID to present the keys as belonging to
+ */
+export function getTestOlmAccountKeys(olmAccount: Olm.Account, userId: string, deviceId: string): IDeviceKeys {
+    const testE2eKeys = JSON.parse(olmAccount.identity_keys());
+    const testDeviceKeys: IDeviceKeys = {
+        algorithms: ["m.olm.v1.curve25519-aes-sha2", "m.megolm.v1.aes-sha2"],
+        device_id: deviceId,
+        keys: {
+            [`curve25519:${deviceId}`]: testE2eKeys.curve25519,
+            [`ed25519:${deviceId}`]: testE2eKeys.ed25519,
+        },
+        user_id: userId,
+    };
+
+    const j = anotherjson.stringify(testDeviceKeys);
+    const sig = olmAccount.sign(j);
+    testDeviceKeys.signatures = { [userId]: { [`ed25519:${deviceId}`]: sig } };
+    return testDeviceKeys;
+}
+
+/**
+ * Bootstrap cross signing for the given Olm account.
+ *
+ * Will generate the cross signing keys and sign them with the master key, and returns the `IDownloadKeyResult`
+ * that can be directly fed into a test e2eKeyResponder.
+ *
+ * The cross-signing keys are randomly generated, similar to how the olm account keys are generated. There may not
+ * be any value in using static vectors, as the device keys change at every test run.
+ *
+ * If some `KeyBackupInfo` are provided, the `auth_data` of each backup info will be signed with the
+ * master key, meaning the backups will be then trusted after verification.
+ *
+ * @param olmAccount - The Olm account object to use for signing the device keys.
+ * @param userId - The user ID to associate with the device keys.
+ * @param deviceId - The device ID to associate with the device keys.
+ * @param keyBackupInfo - Optional key backup infos to sign with the master key.
+ * @returns A valid keys/query response that can be fed into a test e2eKeyResponder.
+ */
+export function bootstrapCrossSigningTestOlmAccount(
+    olmAccount: Olm.Account,
+    userId: string,
+    deviceId: string,
+    keyBackupInfo: KeyBackupInfo[] = [],
+): Partial<IDownloadKeyResult> {
+    const olmAliceMSK = new global.Olm.PkSigning();
+    const masterPrivkey = olmAliceMSK.generate_seed();
+    const masterPubkey = olmAliceMSK.init_with_seed(masterPrivkey);
+
+    const olmAliceUSK = new global.Olm.PkSigning();
+    const userPrivkey = olmAliceUSK.generate_seed();
+    const userPubkey = olmAliceUSK.init_with_seed(userPrivkey);
+
+    const olmAliceSSK = new global.Olm.PkSigning();
+    const sskPrivkey = olmAliceSSK.generate_seed();
+    const sskPubkey = olmAliceSSK.init_with_seed(sskPrivkey);
+
+    const mskInfo: Keys = {
+        user_id: userId,
+        usage: ["master"],
+        keys: {
+            ["ed25519:" + masterPubkey]: masterPubkey,
+        },
+    };
+
+    const sskInfo: Partial<SigningKeys> = {
+        user_id: userId,
+        usage: ["self_signing"],
+        keys: {
+            ["ed25519:" + sskPubkey]: sskPubkey,
+        },
+    };
+    // sign the ssk with the msk
+    const sskSig = olmAliceMSK.sign(anotherjson.stringify(sskInfo));
+    sskInfo.signatures = {
+        [userId]: {
+            ["ed25519:" + masterPubkey]: sskSig,
+        },
+    };
+
+    const uskInfo: Partial<SigningKeys> = {
+        user_id: userId,
+        usage: ["user_signing"],
+        keys: {
+            ["ed25519:" + userPubkey]: userPubkey,
+        },
+    };
+
+    // sign the usk with the msk
+    const uskSig = olmAliceMSK.sign(anotherjson.stringify(uskInfo));
+    uskInfo.signatures = {
+        [userId]: {
+            ["ed25519:" + masterPubkey]: uskSig,
+        },
+    };
+
+    // get the device keys and sign them with the ssk (the device is then cross signed)
+    const deviceKeys = getTestOlmAccountKeys(olmAccount, userId, deviceId);
+
+    const copy = Object.assign({}, deviceKeys);
+    delete copy.signatures;
+    const crossSignature = olmAliceSSK.sign(anotherjson.stringify(copy));
+
+    // add the signature
+    deviceKeys.signatures![userId]["ed25519:" + sskPubkey] = crossSignature;
+
+    // if we have some key backup info, sign them with the msk
+    keyBackupInfo.forEach((info) => {
+        const unsignedAuthData = Object.assign({}, info.auth_data);
+        delete unsignedAuthData.signatures;
+        const backupSignature = olmAliceMSK.sign(anotherjson.stringify(unsignedAuthData));
+
+        info.auth_data.signatures = {
+            [userId]: {
+                ["ed25519:" + masterPubkey]: backupSignature,
+            },
+        };
+    });
+
+    // clean the olm resources as we don't need them anymore
+    olmAliceMSK.free();
+    olmAliceSSK.free();
+    olmAliceUSK.free();
+
+    return {
+        master_keys: { [userId]: mskInfo },
+        user_signing_keys: { [userId]: uskInfo as SigningKeys },
+        self_signing_keys: { [userId]: sskInfo as SigningKeys },
+        device_keys: { [userId]: { [deviceId]: deviceKeys } },
+    };
+}
+
+/** start an Olm session with a given recipient */
+export async function createOlmSession(
+    olmAccount: Olm.Account,
+    recipientTestClient: IE2EKeyReceiver,
+): Promise<Olm.Session> {
+    const keys = await recipientTestClient.awaitOneTimeKeyUpload();
+    const otkId = Object.keys(keys)[0];
+    const otk = keys[otkId];
+
+    const session = new global.Olm.Session();
+    session.create_outbound(olmAccount, recipientTestClient.getDeviceKey(), otk.key);
+    return session;
+}
+
+// IToDeviceEvent isn't exported by src/sync-accumulator.ts
+export interface ToDeviceEvent {
+    content: IContent;
+    sender: string;
+    type: string;
+}
+
+/** encrypt an event with an existing olm session */
+export function encryptOlmEvent(opts: {
+    /** the sender's user id */
+    sender?: string;
+    /** the sender's curve25519 key */
+    senderKey: string;
+    /** the sender's ed25519 key */
+    senderSigningKey: string;
+    /** the olm session to use for encryption */
+    p2pSession: Olm.Session;
+    /** the recipient's user id */
+    recipient: string;
+    /** the recipient's curve25519 key */
+    recipientCurve25519Key: string;
+    /** the recipient's ed25519 key */
+    recipientEd25519Key: string;
+    /** the payload of the message */
+    plaincontent?: object;
+    /** the event type of the payload */
+    plaintype?: string;
+}): ToDeviceEvent {
+    expect(opts.senderKey).toBeTruthy();
+    expect(opts.p2pSession).toBeTruthy();
+    expect(opts.recipient).toBeTruthy();
+
+    const plaintext = {
+        content: opts.plaincontent || {},
+        recipient: opts.recipient,
+        recipient_keys: {
+            ed25519: opts.recipientEd25519Key,
+        },
+        keys: {
+            ed25519: opts.senderSigningKey,
+        },
+        sender: opts.sender || "@bob:xyz",
+        type: opts.plaintype || "m.test",
+    };
+
+    return {
+        content: {
+            algorithm: "m.olm.v1.curve25519-aes-sha2",
+            ciphertext: {
+                [opts.recipientCurve25519Key]: opts.p2pSession.encrypt(JSON.stringify(plaintext)),
+            },
+            sender_key: opts.senderKey,
+        },
+        sender: opts.sender || "@bob:xyz",
+        type: "m.room.encrypted",
+    };
+}
+
+// encrypt an event with megolm
+export function encryptMegolmEvent(opts: {
+    senderKey: string;
+    groupSession: Olm.OutboundGroupSession;
+    plaintext?: Partial<IEvent>;
+    room_id?: string;
+}): IEvent {
+    expect(opts.senderKey).toBeTruthy();
+    expect(opts.groupSession).toBeTruthy();
+
+    const plaintext = opts.plaintext || {};
+    if (!plaintext.content) {
+        plaintext.content = {
+            body: "42",
+            msgtype: "m.text",
+        };
+    }
+    if (!plaintext.type) {
+        plaintext.type = "m.room.message";
+    }
+    if (!plaintext.room_id) {
+        expect(opts.room_id).toBeTruthy();
+        plaintext.room_id = opts.room_id;
+    }
+    return encryptMegolmEventRawPlainText({
+        senderKey: opts.senderKey,
+        groupSession: opts.groupSession,
+        plaintext,
+    });
+}
+
+export function encryptMegolmEventRawPlainText(opts: {
+    senderKey: string;
+    groupSession: Olm.OutboundGroupSession;
+    plaintext: Partial<IEvent>;
+    origin_server_ts?: number;
+}): IEvent {
+    return {
+        event_id: "$test_megolm_event_" + Math.random(),
+        sender: opts.plaintext.sender ?? "@not_the_real_sender:example.com",
+        origin_server_ts: opts.plaintext.origin_server_ts ?? 1672944778000,
+        content: {
+            algorithm: "m.megolm.v1.aes-sha2",
+            ciphertext: opts.groupSession.encrypt(JSON.stringify(opts.plaintext)),
+            device_id: "testDevice",
+            sender_key: opts.senderKey,
+            session_id: opts.groupSession.session_id(),
+        },
+        type: "m.room.encrypted",
+        unsigned: {},
+    };
+}
+
+/** build an encrypted room_key event to share a group session, using an existing olm session */
+export function encryptGroupSessionKey(opts: {
+    /** recipient's user id */
+    recipient: string;
+    /** the recipient's curve25519 key */
+    recipientCurve25519Key: string;
+    /** the recipient's ed25519 key */
+    recipientEd25519Key: string;
+    /** sender's olm account */
+    olmAccount: Olm.Account;
+    /** sender's olm session with the recipient */
+    p2pSession: Olm.Session;
+    groupSession: Olm.OutboundGroupSession;
+    room_id?: string;
+}): ToDeviceEvent {
+    const senderKeys = JSON.parse(opts.olmAccount.identity_keys());
+    return encryptOlmEvent({
+        senderKey: senderKeys.curve25519,
+        senderSigningKey: senderKeys.ed25519,
+        recipient: opts.recipient,
+        recipientCurve25519Key: opts.recipientCurve25519Key,
+        recipientEd25519Key: opts.recipientEd25519Key,
+        p2pSession: opts.p2pSession,
+        plaincontent: {
+            algorithm: "m.megolm.v1.aes-sha2",
+            room_id: opts.room_id,
+            session_id: opts.groupSession.session_id(),
+            session_key: opts.groupSession.session_key(),
+        },
+        plaintype: "m.room_key",
+    });
+}
+
+/**
+ * Test utility to correctly encrypt a secret send event to a test device using the provided p2p session.
+ *
+ * @param opts - the options for the secret send event
+ * @returns the to-device event, ready to be returned in a sync response for the test device.
+ */
+export function encryptSecretSend(opts: {
+    /** the sender's user id */
+    sender: string;
+    /** recipient's user id */
+    recipient: string;
+    /** the recipient's curve25519 key */
+    recipientCurve25519Key: string;
+    /** the recipient's ed25519 key */
+    recipientEd25519Key: string;
+    /** sender's olm account */
+    olmAccount: Olm.Account;
+    /** sender's olm session with the recipient */
+    p2pSession: Olm.Session;
+    /** The requestId of the secret request that this secret send is replying. */
+    requestId: string;
+    /** The secret value */
+    secret: string;
+}): ToDeviceEvent {
+    const senderKeys = JSON.parse(opts.olmAccount.identity_keys());
+    return encryptOlmEvent({
+        sender: opts.sender,
+        senderKey: senderKeys.curve25519,
+        senderSigningKey: senderKeys.ed25519,
+        recipient: opts.recipient,
+        recipientCurve25519Key: opts.recipientCurve25519Key,
+        recipientEd25519Key: opts.recipientEd25519Key,
+        p2pSession: opts.p2pSession,
+        plaincontent: {
+            request_id: opts.requestId,
+            secret: opts.secret,
+        },
+        plaintype: "m.secret.send",
+    });
+}
+
+/**
+ * Establish an Olm Session with the test user
+ *
+ * Waits for the test user to upload their keys, then sends a /sync response with a to-device message which will
+ * establish an Olm session.
+ *
+ * @param testClient - the MatrixClient under test, which we expect to upload account keys, and to make a
+ *    /sync request which we will respond to.
+ * @param keyReceiver - an IE2EKeyReceiver which will intercept the /keys/upload request from the client under test
+ * @param syncResponder - an ISyncResponder which will intercept /sync requests from the client under test
+ * @param peerOlmAccount: an OlmAccount which will be used to initiate the Olm session.
+ */
+export async function establishOlmSession(
+    testClient: MatrixClient,
+    keyReceiver: IE2EKeyReceiver,
+    syncResponder: ISyncResponder,
+    peerOlmAccount: Olm.Account,
+): Promise<Olm.Session> {
+    const peerE2EKeys = JSON.parse(peerOlmAccount.identity_keys());
+    const p2pSession = await createOlmSession(peerOlmAccount, keyReceiver);
+    const olmEvent = encryptOlmEvent({
+        senderKey: peerE2EKeys.curve25519,
+        senderSigningKey: peerE2EKeys.ed25519,
+        recipient: testClient.getUserId()!,
+        recipientCurve25519Key: keyReceiver.getDeviceKey(),
+        recipientEd25519Key: keyReceiver.getSigningKey(),
+        p2pSession: p2pSession,
+    });
+    syncResponder.sendOrQueueSyncResponse({
+        next_batch: 1,
+        to_device: { events: [olmEvent] },
+    });
+    await syncPromise(testClient);
+    return p2pSession;
+}
@@ -41,7 +41,7 @@ describe("MatrixClient.initRustCrypto", () => {
        await expect(() => unknownDeviceClient.initRustCrypto()).rejects.toThrow("unknown deviceId");
    });

-    it("should create the indexed dbs", async () => {
+    it("should create the indexed db", async () => {
        const matrixClient = createClient({
            baseUrl: "http://test.server",
            userId: "@alice:localhost",
@@ -53,7 +53,25 @@ describe("MatrixClient.initRustCrypto", () => {

        await matrixClient.initRustCrypto();

-        // should have two dbs now
+        // should have an indexed db now
+        const databaseNames = (await indexedDB.databases()).map((db) => db.name);
+        expect(databaseNames).toEqual(expect.arrayContaining(["matrix-js-sdk::matrix-sdk-crypto"]));
+    });
+
+    it("should create the meta db if given a pickleKey", async () => {
+        const matrixClient = createClient({
+            baseUrl: "http://test.server",
+            userId: "@alice:localhost",
+            deviceId: "aliceDevice",
+            pickleKey: "testKey",
+        });
+
+        // No databases.
+        expect(await indexedDB.databases()).toHaveLength(0);
+
+        await matrixClient.initRustCrypto();
+
+        // should have two indexed dbs now
        const databaseNames = (await indexedDB.databases()).map((db) => db.name);
        expect(databaseNames).toEqual(
            expect.arrayContaining(["matrix-js-sdk::matrix-sdk-crypto", "matrix-js-sdk::matrix-sdk-crypto-meta"]),
@@ -78,6 +96,7 @@ describe("MatrixClient.clearStores", () => {
            baseUrl: "http://test.server",
            userId: "@alice:localhost",
            deviceId: "aliceDevice",
+            pickleKey: "testKey",
        });

        await matrixClient.initRustCrypto();
@@ -21,12 +21,15 @@ import { MockResponse } from "fetch-mock";
 import fetchMock from "fetch-mock-jest";
 import { IDBFactory } from "fake-indexeddb";
 import { createHash } from "crypto";
+import Olm from "@matrix-org/olm";

 import {
    createClient,
    CryptoEvent,
+    DeviceVerification,
    IContent,
    ICreateClientOpts,
+    IEvent,
    MatrixClient,
    MatrixEvent,
    MatrixEventEvent,
@@ -41,13 +44,23 @@ import {
    Verifier,
    VerifierEvent,
 } from "../../../src/crypto-api/verification";
-import { escapeRegExp } from "../../../src/utils";
-import { CRYPTO_BACKENDS, emitPromise, getSyncResponse, InitCrypto, syncPromise } from "../../test-utils/test-utils";
+import { defer, escapeRegExp } from "../../../src/utils";
+import {
+    awaitDecryption,
+    CRYPTO_BACKENDS,
+    emitPromise,
+    getSyncResponse,
+    InitCrypto,
+    syncPromise,
+} from "../../test-utils/test-utils";
 import { SyncResponder } from "../../test-utils/SyncResponder";
 import {
+    BACKUP_DECRYPTION_KEY_BASE64,
+    BOB_ONE_TIME_KEYS,
    BOB_SIGNED_CROSS_SIGNING_KEYS_DATA,
    BOB_SIGNED_TEST_DEVICE_DATA,
    BOB_TEST_USER_ID,
+    CURVE25519_KEY_BACKUP_DATA,
    MASTER_CROSS_SIGNING_PUBLIC_KEY_BASE64,
    SIGNED_CROSS_SIGNING_KEYS_DATA,
    SIGNED_TEST_DEVICE_DATA,
@@ -55,11 +68,20 @@ import {
    TEST_DEVICE_PUBLIC_ED25519_KEY_BASE64,
    TEST_ROOM_ID,
    TEST_USER_ID,
-    BOB_ONE_TIME_KEYS,
 } from "../../test-utils/test-data";
 import { mockInitialApiRequests } from "../../test-utils/mockEndpoints";
 import { E2EKeyResponder } from "../../test-utils/E2EKeyResponder";
 import { E2EKeyReceiver } from "../../test-utils/E2EKeyReceiver";
+import {
+    bootstrapCrossSigningTestOlmAccount,
+    createOlmSession,
+    encryptGroupSessionKey,
+    encryptMegolmEvent,
+    encryptSecretSend,
+    ToDeviceEvent,
+} from "./olm-utils";
+import { KeyBackupInfo } from "../../../src/crypto-api";
+import { encodeBase64 } from "../../../src/base64";

 // The verification flows use javascript timers to set timeouts. We tell jest to use mock timer implementations
 // to ensure that we don't end up with dangling timeouts.
@@ -138,6 +160,12 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("verification (%s)", (backend: st
        beforeEach(async () => {
            // pretend that we have another device, which we will verify
            e2eKeyResponder.addDeviceKeys(SIGNED_TEST_DEVICE_DATA);
+
+            fetchMock.put(
+                new RegExp(`/_matrix/client/(r0|v3)/sendToDevice/${escapeRegExp("m.secret.request")}`),
+                { ok: false, status: 404 },
+                { overwriteRoutes: true },
+            );
        });

        // test with (1) the default verification method list, (2) a custom verification method list.
@@ -409,6 +437,15 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("verification (%s)", (backend: st
        });

        it("can verify another via QR code with an untrusted cross-signing key", async () => {
+            // This is a slightly weird thing to test; if we don't trust the cross-signing key, normally we would
+            // spam out a verification request to all devices rather than targeting a single device. Still, it's
+            // a thing both the Matrix protocol and the js-sdk API support, so we may as well test it.
+            //
+            // Since we don't yet trust the master key, this is a type 0x02 QR code:
+            //   "self-verifying in which the current device does not yet trust the master key"
+            //
+            // By the end of it, we should trust the master key.
+
            aliceClient = await startTestClient();
            // QRCode fails if we don't yet have the cross-signing keys, so make sure we have them now.
            e2eKeyResponder.addCrossSigningData(SIGNED_CROSS_SIGNING_KEYS_DATA);
@@ -480,12 +517,51 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("verification (%s)", (backend: st
            reciprocateQRCodeCallbacks.confirm();
            await sendToDevicePromise;

+            // at this point, on legacy crypto, the master key is already marked as trusted, and the request is "Done".
+            // Rust crypto, on the other hand, waits for the 'done' to arrive from the other side.
+            if (request.phase === VerificationPhase.Done) {
+                // legacy crypto: we're all done
+                const userVerificationStatus = await aliceClient.getCrypto()!.getUserVerificationStatus(TEST_USER_ID);
+                // eslint-disable-next-line jest/no-conditional-expect
+                expect(userVerificationStatus.isCrossSigningVerified()).toBeTruthy();
+                await verificationPromise;
+            } else {
+                // rust crypto: still in flight
+                // eslint-disable-next-line jest/no-conditional-expect
+                expect(request.phase).toEqual(VerificationPhase.Started);
+            }
+
            // the dummy device replies with its own 'done'
            returnToDeviceMessageFromSync(buildDoneMessage(transactionId));

-            // ... and the whole thing should be done!
+            // ... and now we're really done.
            await verificationPromise;
            expect(request.phase).toEqual(VerificationPhase.Done);
+            const userVerificationStatus = await aliceClient.getCrypto()!.getUserVerificationStatus(TEST_USER_ID);
+            expect(userVerificationStatus.isCrossSigningVerified()).toBeTruthy();
+        });
+
+        it("can try to generate a QR code when QR code is not supported", async () => {
+            aliceClient = await startTestClient();
+            // we need cross-signing keys for a QR code verification
+            e2eKeyResponder.addCrossSigningData(SIGNED_CROSS_SIGNING_KEYS_DATA);
+            await waitForDeviceList();
+
+            // Alice sends a m.key.verification.request
+            const [, request] = await Promise.all([
+                expectSendToDeviceMessage("m.key.verification.request"),
+                aliceClient.getCrypto()!.requestDeviceVerification(TEST_USER_ID, TEST_DEVICE_ID),
+            ]);
+            const transactionId = request.transactionId!;
+
+            // The dummy device replies with an m.key.verification.ready, indicating it can only use SaS
+            returnToDeviceMessageFromSync(buildReadyMessage(transactionId, ["m.sas.v1"]));
+            await waitForVerificationRequestChanged(request);
+            expect(request.phase).toEqual(VerificationPhase.Ready);
+
+            // Alice tries to generate a QR Code but it's unavailable
+            const qrCodeBuffer = await request.generateQRCode();
+            expect(qrCodeBuffer).toBeUndefined();
        });

        newBackendOnly("can verify another by scanning their QR code", async () => {
@@ -897,6 +973,488 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("verification (%s)", (backend: st
        });
    });

+    describe("Incoming verification in a DM", () => {
+        let testOlmAccount: Olm.Account;
+
+        beforeEach(async () => {
+            // create a test olm device which we will use to communicate with alice. We use libolm to implement this.
+            await Olm.init();
+            testOlmAccount = new Olm.Account();
+            testOlmAccount.create();
+
+            aliceClient = await startTestClient();
+            aliceClient.setGlobalErrorOnUnknownDevices(false);
+            syncResponder.sendOrQueueSyncResponse(getSyncResponse([BOB_TEST_USER_ID]));
+            await syncPromise(aliceClient);
+        });
+
+        /**
+         * Return a plaintext verification request event from Bob to Alice
+         * @see https://spec.matrix.org/v1.7/client-server-api/#mkeyverificationrequest
+         */
+        function createVerificationRequestEvent(): IEvent {
+            return {
+                content: {
+                    body: "Verification request from Bob to Alice",
+                    from_device: "BobDevice",
+                    methods: ["m.sas.v1"],
+                    msgtype: "m.key.verification.request",
+                    to: aliceClient.getUserId()!,
+                },
+                event_id: "$143273582443PhrSn:example.org",
+                origin_server_ts: Date.now(),
+                room_id: TEST_ROOM_ID,
+                sender: "@bob:xyz",
+                type: "m.room.message",
+                unsigned: {
+                    age: 1234,
+                },
+            };
+        }
+
+        /**
+         * Create a to-device event from Bob to Alice, sharing the group session key
+         * @param groupSession - group session key to share
+         * @param p2pSession - test Olm session to encrypt the key with
+         */
+        function encryptGroupSessionKeyForAlice(
+            groupSession: Olm.OutboundGroupSession,
+            p2pSession: Olm.Session,
+        ): ToDeviceEvent {
+            return encryptGroupSessionKey({
+                recipient: aliceClient.getUserId()!,
+                recipientCurve25519Key: e2eKeyReceiver.getDeviceKey(),
+                recipientEd25519Key: e2eKeyReceiver.getSigningKey(),
+                olmAccount: testOlmAccount,
+                p2pSession: p2pSession,
+                groupSession: groupSession,
+                room_id: TEST_ROOM_ID,
+            });
+        }
+
+        /**
+         * Create and encrypt a verification request event
+         * @param groupSession
+         */
+        function createEncryptedVerificationRequest(groupSession: Olm.OutboundGroupSession): IEvent {
+            const testOlmAccountKeys = JSON.parse(testOlmAccount.identity_keys());
+            return encryptMegolmEvent({
+                senderKey: testOlmAccountKeys.curve25519,
+                groupSession: groupSession,
+                room_id: TEST_ROOM_ID,
+                plaintext: createVerificationRequestEvent(),
+            });
+        }
+
+        it("Verification request not found", async () => {
+            // Expect to not find any verification request
+            const request = aliceClient.getCrypto()!.findVerificationRequestDMInProgress(TEST_ROOM_ID, "@bob:xyz");
+            expect(request).toBeUndefined();
+        });
+
+        it("ignores old verification requests", async () => {
+            const eventHandler = jest.fn();
+            aliceClient.on(CryptoEvent.VerificationRequestReceived, eventHandler);
+
+            const verificationRequestEvent = createVerificationRequestEvent();
+            verificationRequestEvent.origin_server_ts -= 1000000;
+            returnRoomMessageFromSync(TEST_ROOM_ID, verificationRequestEvent);
+
+            await syncPromise(aliceClient);
+
+            // make sure the event has arrived
+            const room = aliceClient.getRoom(TEST_ROOM_ID)!;
+            const matrixEvent = room.getLiveTimeline().getEvents()[0];
+            expect(matrixEvent.getId()).toEqual(verificationRequestEvent.event_id);
+
+            // check that an event has not been raised, and that the request is not found
+            expect(eventHandler).not.toHaveBeenCalled();
+            expect(
+                aliceClient.getCrypto()!.findVerificationRequestDMInProgress(TEST_ROOM_ID, "@bob:xyz"),
+            ).not.toBeDefined();
+        });
+
+        it("Plaintext verification request from Bob to Alice", async () => {
+            // Add verification request from Bob to Alice in the DM between them
+            returnRoomMessageFromSync(TEST_ROOM_ID, createVerificationRequestEvent());
+
+            // Wait for the request to be received
+            const request1 = await emitPromise(aliceClient, CryptoEvent.VerificationRequestReceived);
+            expect(request1.roomId).toBe(TEST_ROOM_ID);
+            expect(request1.isSelfVerification).toBe(false);
+            expect(request1.otherUserId).toBe("@bob:xyz");
+
+            const request = aliceClient.getCrypto()!.findVerificationRequestDMInProgress(TEST_ROOM_ID, "@bob:xyz");
+            // Expect to find the verification request received during the sync
+            expect(request?.roomId).toBe(TEST_ROOM_ID);
+            expect(request?.isSelfVerification).toBe(false);
+            expect(request?.otherUserId).toBe("@bob:xyz");
+        });
+
+        it("Encrypted verification request from Bob to Alice", async () => {
+            const p2pSession = await createOlmSession(testOlmAccount, e2eKeyReceiver);
+            const groupSession = new Olm.OutboundGroupSession();
+            groupSession.create();
+
+            // make the room_key event, but don't send it yet
+            const toDeviceEvent = encryptGroupSessionKeyForAlice(groupSession, p2pSession);
+
+            // Add verification request from Bob to Alice in the DM between them
+            returnRoomMessageFromSync(TEST_ROOM_ID, createEncryptedVerificationRequest(groupSession));
+
+            // Wait for the sync response to be processed
+            await syncPromise(aliceClient);
+
+            const room = aliceClient.getRoom(TEST_ROOM_ID)!;
+            const matrixEvent = room.getLiveTimeline().getEvents()[0];
+
+            // wait for a first attempt at decryption: should fail
+            await awaitDecryption(matrixEvent);
+            expect(matrixEvent.getContent().msgtype).toEqual("m.bad.encrypted");
+
+            const requestEventPromise = emitPromise(aliceClient, CryptoEvent.VerificationRequestReceived);
+
+            // Send Bob the room keys
+            returnToDeviceMessageFromSync(toDeviceEvent);
+
+            // advance the clock, because the devicelist likes to sleep for 5ms during key downloads
+            await jest.advanceTimersByTimeAsync(10);
+
+            // Wait for the request to be decrypted
+            const request1 = await requestEventPromise;
+            expect(request1.roomId).toBe(TEST_ROOM_ID);
+            expect(request1.isSelfVerification).toBe(false);
+            expect(request1.otherUserId).toBe("@bob:xyz");
+
+            const request = aliceClient.getCrypto()!.findVerificationRequestDMInProgress(TEST_ROOM_ID, "@bob:xyz");
+            // Expect to find the verification request received during the sync
+            expect(request?.roomId).toBe(TEST_ROOM_ID);
+            expect(request?.isSelfVerification).toBe(false);
+            expect(request?.otherUserId).toBe("@bob:xyz");
+        });
+
+        newBackendOnly(
+            "If the verification request is not decrypted within 5 minutes, the request is ignored",
+            async () => {
+                const p2pSession = await createOlmSession(testOlmAccount, e2eKeyReceiver);
+                const groupSession = new Olm.OutboundGroupSession();
+                groupSession.create();
+
+                // make the room_key event, but don't send it yet
+                const toDeviceEvent = encryptGroupSessionKeyForAlice(groupSession, p2pSession);
+
+                // Add verification request from Bob to Alice in the DM between them
+                returnRoomMessageFromSync(TEST_ROOM_ID, createEncryptedVerificationRequest(groupSession));
+
+                // Wait for the sync response to be processed
+                await syncPromise(aliceClient);
+
+                const room = aliceClient.getRoom(TEST_ROOM_ID)!;
+                const matrixEvent = room.getLiveTimeline().getEvents()[0];
+
+                // wait for a first attempt at decryption: should fail
+                await awaitDecryption(matrixEvent);
+                expect(matrixEvent.getContent().msgtype).toEqual("m.bad.encrypted");
+
+                // Advance time by 5mins, the verification request should be ignored after that
+                jest.advanceTimersByTime(5 * 60 * 1000);
+
+                // Send Bob the room keys
+                returnToDeviceMessageFromSync(toDeviceEvent);
+
+                // Wait for the message to be decrypted
+                await awaitDecryption(matrixEvent, { waitOnDecryptionFailure: true });
+
+                const request = aliceClient.getCrypto()!.findVerificationRequestDMInProgress(TEST_ROOM_ID, "@bob:xyz");
+                // the request should not be present
+                expect(request).not.toBeDefined();
+            },
+        );
+    });
+
+    describe("Secrets are gossiped after verification", () => {
+        // We use a legacy olm session as the existing session.
+        // This will give us access to low level olm functions in order to
+        // simulate a backup key request with proper olm encryption.
+        let testOlmAccount: Olm.Account;
+        const olmDeviceId = "OLM_DEVICE";
+        let usermasterPubKey: string;
+
+        const matchingBackupInfo: KeyBackupInfo = {
+            algorithm: "m.megolm_backup.v1.curve25519-aes-sha2",
+            version: "1",
+            auth_data: {
+                public_key: "hSDwCYkwp1R0i33ctD73Wg2/Og0mOBr066SpjqqbTmo",
+            },
+        };
+
+        const nonMatchingBackupInfo: KeyBackupInfo = {
+            algorithm: "m.megolm_backup.v1.curve25519-aes-sha2",
+            version: "1",
+            auth_data: {
+                public_key: "EjDwCYkwp1R0i33ctD73Wg2/Og0mOBr066Spjqqaqqo",
+            },
+        };
+
+        const unknownAlgorithmBackupInfo: KeyBackupInfo = {
+            algorithm: "m.megolm_backup.foo_bar",
+            version: "1",
+            auth_data: {
+                public_key: "EjDwCYkwp1R0i33ctD73Wg2/Og0mOBr066Spjqqaqqo",
+            },
+        };
+
+        beforeEach(async () => {
+            // create a test olm device which we will use to communicate with alice. We use libolm to implement this.
+            await Olm.init();
+            testOlmAccount = new Olm.Account();
+            testOlmAccount.create();
+
+            const bootstrapped = bootstrapCrossSigningTestOlmAccount(testOlmAccount, TEST_USER_ID, olmDeviceId, [
+                matchingBackupInfo,
+                nonMatchingBackupInfo,
+            ]);
+
+            e2eKeyResponder.addDeviceKeys(bootstrapped.device_keys![TEST_USER_ID]![olmDeviceId]);
+            e2eKeyResponder.addCrossSigningData(bootstrapped);
+
+            usermasterPubKey = Object.values(bootstrapped.master_keys![TEST_USER_ID].keys)[0];
+
+            aliceClient = await startTestClient();
+            syncResponder.sendOrQueueSyncResponse(getSyncResponse([TEST_USER_ID]));
+            await syncPromise(aliceClient);
+            // DeviceList has a sleep(5) which we need to make happen
+            await jest.advanceTimersByTimeAsync(10);
+
+            // The client should now know about the olm device
+            const devices = await aliceClient.getCrypto()!.getUserDeviceInfo([TEST_USER_ID]);
+            expect(devices.get(TEST_USER_ID)!.keys()).toContain(olmDeviceId);
+        });
+
+        afterEach(async () => {
+            aliceClient?.stopClient();
+            testOlmAccount?.free();
+
+            // Allow in-flight things to complete before we tear down the test
+            await jest.runAllTimersAsync();
+
+            fetchMock.mockReset();
+        });
+
+        newBackendOnly("Should request cross signing keys after verification", async () => {
+            const requestPromises = mockSecretRequestAndGetPromises();
+
+            await doInteractiveVerification();
+
+            // The secret must have been requested
+            await requestPromises.get("m.cross_signing.master");
+            await requestPromises.get("m.cross_signing.user_signing");
+            await requestPromises.get("m.cross_signing.self_signing");
+        });
+
+        newBackendOnly("Should accept the backup decryption key gossip if valid", async () => {
+            const requestPromises = mockSecretRequestAndGetPromises();
+
+            await doInteractiveVerification();
+
+            const requestId = await requestPromises.get("m.megolm_backup.v1");
+
+            const keyBackupIsCached = emitPromise(aliceClient, CryptoEvent.KeyBackupDecryptionKeyCached);
+
+            await sendBackupGossipAndExpectVersion(requestId!, BACKUP_DECRYPTION_KEY_BASE64, matchingBackupInfo);
+
+            await keyBackupIsCached;
+
+            // the backup secret should be cached
+            const cachedKey = await aliceClient.getCrypto()!.getSessionBackupPrivateKey();
+            expect(cachedKey).toBeTruthy();
+            expect(encodeBase64(cachedKey!)).toEqual(BACKUP_DECRYPTION_KEY_BASE64);
+        });
+
+        newBackendOnly("Should not accept the backup decryption key gossip if private key do not match", async () => {
+            const requestPromises = mockSecretRequestAndGetPromises();
+
+            await doInteractiveVerification();
+
+            const requestId = await requestPromises.get("m.megolm_backup.v1");
+
+            await sendBackupGossipAndExpectVersion(requestId!, BACKUP_DECRYPTION_KEY_BASE64, nonMatchingBackupInfo);
+
+            // We are lacking a way to signal that the secret has been received, so we wait a bit..
+            jest.useRealTimers();
+            await new Promise((resolve) => {
+                setTimeout(resolve, 500);
+            });
+            jest.useFakeTimers();
+
+            // the backup secret should not be cached
+            const cachedKey = await aliceClient.getCrypto()!.getSessionBackupPrivateKey();
+            expect(cachedKey).toBeNull();
+        });
+
+        newBackendOnly("Should not accept the backup decryption key gossip if backup not trusted", async () => {
+            const requestPromises = mockSecretRequestAndGetPromises();
+
+            await doInteractiveVerification();
+
+            const requestId = await requestPromises.get("m.megolm_backup.v1");
+
+            const infoCopy = Object.assign({}, matchingBackupInfo);
+            delete infoCopy.auth_data.signatures;
+
+            await sendBackupGossipAndExpectVersion(requestId!, BACKUP_DECRYPTION_KEY_BASE64, infoCopy);
+
+            // We are lacking a way to signal that the secret has been received, so we wait a bit..
+            jest.useRealTimers();
+            await new Promise((resolve) => {
+                setTimeout(resolve, 500);
+            });
+            jest.useFakeTimers();
+
+            // the backup secret should not be cached
+            const cachedKey = await aliceClient.getCrypto()!.getSessionBackupPrivateKey();
+            expect(cachedKey).toBeNull();
+        });
+
+        newBackendOnly("Should not accept the backup decryption key gossip if backup algorithm unknown", async () => {
+            const requestPromises = mockSecretRequestAndGetPromises();
+
+            await doInteractiveVerification();
+
+            const requestId = await requestPromises.get("m.megolm_backup.v1");
+
+            await sendBackupGossipAndExpectVersion(
+                requestId!,
+                BACKUP_DECRYPTION_KEY_BASE64,
+                unknownAlgorithmBackupInfo,
+            );
+
+            // We are lacking a way to signal that the secret has been received, so we wait a bit..
+            jest.useRealTimers();
+            await new Promise((resolve) => {
+                setTimeout(resolve, 500);
+            });
+            jest.useFakeTimers();
+
+            // the backup secret should not be cached
+            const cachedKey = await aliceClient.getCrypto()!.getSessionBackupPrivateKey();
+            expect(cachedKey).toBeNull();
+        });
+
+        newBackendOnly("Should not accept an invalid backup decryption key", async () => {
+            const requestPromises = mockSecretRequestAndGetPromises();
+
+            await doInteractiveVerification();
+
+            const requestId = await requestPromises.get("m.megolm_backup.v1");
+
+            await sendBackupGossipAndExpectVersion(requestId!, "InvalidSecret", matchingBackupInfo);
+
+            // We are lacking a way to signal that the secret has been received, so we wait a bit..
+            jest.useRealTimers();
+            await new Promise((resolve) => {
+                setTimeout(resolve, 500);
+            });
+            jest.useFakeTimers();
+
+            // the backup secret should not be cached
+            const cachedKey = await aliceClient.getCrypto()!.getSessionBackupPrivateKey();
+            expect(cachedKey).toBeNull();
+        });
+
+        /**
+         * Common test setup for gossiping secrets.
+         * Creates a peer to peer session, sends the secret, mockup the version API, send the secret back from sync, then await for the backup check.
+         */
+        async function sendBackupGossipAndExpectVersion(
+            requestId: string,
+            secret: string,
+            expectBackup: KeyBackupInfo,
+        ) {
+            const p2pSession = await createOlmSession(testOlmAccount, e2eKeyReceiver);
+
+            const toDeviceEvent = encryptSecretSend({
+                sender: aliceClient.getUserId()!,
+                recipient: aliceClient.getUserId()!,
+                recipientCurve25519Key: e2eKeyReceiver.getDeviceKey(),
+                recipientEd25519Key: e2eKeyReceiver.getSigningKey(),
+                p2pSession: p2pSession,
+                olmAccount: testOlmAccount,
+                requestId: requestId!,
+                secret: secret,
+            });
+
+            const expectBackupCheck = new Promise((resolve) => {
+                fetchMock.get(
+                    "express:/_matrix/client/v3/room_keys/version",
+                    (url, request) => {
+                        resolve(undefined);
+                        return expectBackup;
+                    },
+                    {
+                        overwriteRoutes: true,
+                    },
+                );
+            });
+
+            fetchMock.get("express:/_matrix/client/v3/room_keys/keys", CURVE25519_KEY_BACKUP_DATA);
+
+            // The dummy device sends the secret
+            returnToDeviceMessageFromSync(toDeviceEvent);
+
+            await expectBackupCheck;
+        }
+
+        /**
+         * Do an interactive verification between alice and the dummy device.
+         */
+        async function doInteractiveVerification(): Promise<void> {
+            // Do a QR code verification for simplicity
+
+            // Alice sends a m.key.verification.request
+            const [, request] = await Promise.all([
+                expectSendToDeviceMessage("m.key.verification.request"),
+                aliceClient.getCrypto()!.requestDeviceVerification(TEST_USER_ID, olmDeviceId),
+            ]);
+            const transactionId = request.transactionId!;
+
+            // The dummy device replies with an m.key.verification.ready, indicating it can show a QR code
+            returnToDeviceMessageFromSync(
+                buildReadyMessage(transactionId, ["m.qr_code.show.v1", "m.reciprocate.v1"], olmDeviceId),
+            );
+            await waitForVerificationRequestChanged(request);
+
+            const currentDeviceKey = e2eKeyReceiver.getSigningKey();
+            // the dummy device shows a QR code
+            const sharedSecret = "SUPERSEKRET";
+            // use mode 0x01, self-verifying in which the current device does trust the master key
+            const mode = 0x01;
+            const qrCodeBuffer = buildQRCode(transactionId, usermasterPubKey, currentDeviceKey, sharedSecret, mode);
+
+            // Alice scans the QR code
+            const sendToDevicePromise = expectSendToDeviceMessage("m.key.verification.start");
+            const verifier = await request.scanQRCode(qrCodeBuffer);
+
+            await sendToDevicePromise;
+
+            const verificationPromise = verifier.verify();
+            // the dummy device confirms that Alice scanned the QR code, by replying with a done
+            returnToDeviceMessageFromSync(buildDoneMessage(transactionId));
+
+            // Alice also replies with a 'done'
+            await expectSendToDeviceMessage("m.key.verification.done");
+
+            // ... and the whole thing should be done!
+            await verificationPromise;
+
+            // The other device should now be verified.
+            const otherDevice = (await aliceClient.getCrypto()!.getUserDeviceInfo([TEST_USER_ID]))
+                .get(TEST_USER_ID)!
+                .get(olmDeviceId);
+            expect(otherDevice?.verified).toEqual(DeviceVerification.Verified);
+        }
+    });
+
    async function startTestClient(opts: Partial<ICreateClientOpts> = {}): Promise<MatrixClient> {
        const client = createClient({
            baseUrl: TEST_HOMESERVER_URL,
@@ -927,6 +1485,17 @@ describe.each(Object.entries(CRYPTO_BACKENDS))("verification (%s)", (backend: st
        ev.sender ??= TEST_USER_ID;
        syncResponder.sendOrQueueSyncResponse({ to_device: { events: [ev] } });
    }
+
+    function returnRoomMessageFromSync(roomId: string, ev: IEvent): void {
+        syncResponder.sendOrQueueSyncResponse({
+            next_batch: 1,
+            rooms: {
+                join: {
+                    [roomId]: { timeline: { events: [ev] } },
+                },
+            },
+        });
+    }
 });

 /**
@@ -947,6 +1516,52 @@ function expectSendToDeviceMessage(msgtype: string): Promise<{ messages: any }>
    });
 }

+/**
+ * Utility to add all needed mocks for secret requesting (to-device of type `m.secret.request`).
+ *
+ * The following secrets are mocked: `m.cross_signing.master`, `m.cross_signing.self_signing`,
+ * `m.cross_signing.user_signing`, `m.megolm_backup.v1`.
+ *
+ *  @returns a map of secret name to promise that will resolve (with the id of the secret request) when the secret is requested.
+ */
+function mockSecretRequestAndGetPromises(): Map<string, Promise<string>> {
+    const mskRequestDefer = defer<string>();
+    const sskRequestDefer = defer<string>();
+    const uskRequestDefer = defer<string>();
+    const backupKeyRequestDefer = defer<string>();
+
+    fetchMock.put(
+        new RegExp(`/_matrix/client/(r0|v3)/sendToDevice/m.secret.request`),
+        (url: string, opts: RequestInit): MockResponse => {
+            const messages = JSON.parse(opts.body as string).messages[TEST_USER_ID];
+            // rust crypto broadcasts to all devices, old crypto to a specific device, take the first one
+            const content = Object.values(messages)[0] as any;
+            if (content.action == "request") {
+                const name = content.name;
+                const requestId = content.request_id;
+                if (name == "m.cross_signing.user_signing") {
+                    uskRequestDefer.resolve(requestId);
+                } else if (name == "m.cross_signing.master") {
+                    mskRequestDefer.resolve(requestId);
+                } else if (name == "m.cross_signing.self_signing") {
+                    sskRequestDefer.resolve(requestId);
+                } else if (name == "m.megolm_backup.v1") {
+                    backupKeyRequestDefer.resolve(requestId);
+                }
+            }
+            return {};
+        },
+        { overwriteRoutes: true },
+    );
+
+    const promiseMap = new Map<string, Promise<string>>();
+    promiseMap.set("m.cross_signing.master", mskRequestDefer.promise);
+    promiseMap.set("m.cross_signing.self_signing", sskRequestDefer.promise);
+    promiseMap.set("m.cross_signing.user_signing", uskRequestDefer.promise);
+    promiseMap.set("m.megolm_backup.v1", backupKeyRequestDefer.promise);
+    return promiseMap;
+}
+
 /** wait for the verification request to emit a 'Change' event */
 function waitForVerificationRequestChanged(request: VerificationRequest): Promise<void> {
    return new Promise<void>((resolve) => {
@@ -991,12 +1606,16 @@ function buildRequestMessage(transactionId: string): { type: string; content: ob
    };
 }

-/** build an m.key.verification.ready to-device message originating from the dummy device */
-function buildReadyMessage(transactionId: string, methods: string[]): { type: string; content: object } {
+/** build an m.key.verification.ready to-device message originating from the given `fromDevice` (default to `TEST_DEVICE_ID` if not provided) */
+function buildReadyMessage(
+    transactionId: string,
+    methods: string[],
+    fromDevice?: string,
+): { type: string; content: object } {
    return {
        type: "m.key.verification.ready",
        content: {
-            from_device: TEST_DEVICE_ID,
+            from_device: fromDevice || TEST_DEVICE_ID,
            methods: methods,
            transaction_id: transactionId,
        },
@@ -1094,14 +1713,20 @@ function buildDoneMessage(transactionId: string) {
    };
 }

-function buildQRCode(transactionId: string, key1Base64: string, key2Base64: string, sharedSecret: string): Uint8Array {
+function buildQRCode(
+    transactionId: string,
+    key1Base64: string,
+    key2Base64: string,
+    sharedSecret: string,
+    mode = 0x02,
+): Uint8Array {
    // https://spec.matrix.org/v1.7/client-server-api/#qr-code-format

    const qrCodeBuffer = Buffer.alloc(150); // oversize
    let idx = 0;
    idx += qrCodeBuffer.write("MATRIX", idx, "ascii");
    idx = qrCodeBuffer.writeUInt8(0x02, idx); // version
-    idx = qrCodeBuffer.writeUInt8(0x02, idx); // mode
+    idx = qrCodeBuffer.writeUInt8(mode, idx); // mode
    idx = qrCodeBuffer.writeInt16BE(transactionId.length, idx);
    idx += qrCodeBuffer.write(transactionId, idx, "ascii");

@@ -194,6 +194,37 @@ describe("MatrixClient events", function () {
            expect(fired).toBe(true);
        });

+        it("should emit User events when presence data is absent in first sync", async () => {
+            const MODIFIED_SYNC_DATA: any = structuredClone(SYNC_DATA);
+            delete MODIFIED_SYNC_DATA["presence"];
+            const MODIFIED_NEXT_SYNC_DATA: any = structuredClone(NEXT_SYNC_DATA);
+            MODIFIED_NEXT_SYNC_DATA.presence = {
+                events: [
+                    utils.mkPresence({
+                        user: "@foo:bar",
+                        name: "Foo Bar",
+                        presence: "online",
+                    }),
+                ],
+            };
+            httpBackend!.when("GET", "/sync").respond(200, MODIFIED_SYNC_DATA);
+            httpBackend!.when("GET", "/sync").respond(200, MODIFIED_NEXT_SYNC_DATA);
+            let fired = false;
+            client!.on(UserEvent.Presence, function (event, user) {
+                fired = true;
+                expect(user).toBeTruthy();
+                expect(event).toBeTruthy();
+                if (!user || !event) {
+                    return;
+                }
+                expect(event.event).toEqual(MODIFIED_NEXT_SYNC_DATA.presence.events[0]);
+                expect(user.presence).toEqual(MODIFIED_NEXT_SYNC_DATA.presence.events[0]?.content?.presence);
+            });
+            client!.startClient();
+            await httpBackend!.flushAllExpected();
+            expect(fired).toBe(true);
+        });
+
        it("should emit Room events", function () {
            httpBackend!.when("GET", "/sync").respond(200, SYNC_DATA);
            httpBackend!.when("GET", "/sync").respond(200, NEXT_SYNC_DATA);
@@ -33,7 +33,7 @@ import {
 import { logger } from "../../src/logger";
 import { encodeParams, encodeUri, QueryDict, replaceParam } from "../../src/utils";
 import { TestClient } from "../TestClient";
-import { FeatureSupport, Thread, THREAD_RELATION_TYPE, ThreadEvent } from "../../src/models/thread";
+import { FeatureSupport, Thread, ThreadEvent } from "../../src/models/thread";
 import { emitPromise } from "../test-utils/test-utils";
 import { Feature, ServerSupport } from "../../src/feature";

@@ -623,9 +623,7 @@ describe("MatrixClient event timelines", function () {
                    "GET",
                    "/rooms/!foo%3Abar/relations/" +
                        encodeURIComponent(THREAD_ROOT.event_id!) +
-                        "/" +
-                        encodeURIComponent(THREAD_RELATION_TYPE.name) +
-                        buildRelationPaginationQuery({ dir: Direction.Backward, limit: 1 }),
+                        buildRelationPaginationQuery({ dir: Direction.Backward }),
                )
                .respond(200, function () {
                    return {
@@ -1154,10 +1152,7 @@ describe("MatrixClient event timelines", function () {
        httpBackend
            .when(
                "GET",
-                "/_matrix/client/v1/rooms/!foo%3Abar/relations/" +
-                    encodeURIComponent(THREAD_ROOT_UPDATED.event_id!) +
-                    "/" +
-                    encodeURIComponent(THREAD_RELATION_TYPE.name),
+                "/_matrix/client/v1/rooms/!foo%3Abar/relations/" + encodeURIComponent(THREAD_ROOT_UPDATED.event_id!),
            )
            .respond(200, {
                chunk: [THREAD_REPLY3.event, THREAD_REPLY2.event, THREAD_REPLY],
@@ -1262,11 +1257,8 @@ describe("MatrixClient event timelines", function () {
                "GET",
                "/_matrix/client/v1/rooms/!foo%3Abar/relations/" +
                    encodeURIComponent(THREAD_ROOT_UPDATED.event_id!) +
-                    "/" +
-                    encodeURIComponent(THREAD_RELATION_TYPE.name) +
                    buildRelationPaginationQuery({
                        dir: Direction.Backward,
-                        limit: 3,
                        recurse: true,
                    }),
            )
@@ -1321,11 +1313,7 @@ describe("MatrixClient event timelines", function () {
        function respondToThread(root: Partial<IEvent>, replies: Partial<IEvent>[]): ExpectedHttpRequest {
            const request = httpBackend.when(
                "GET",
-                "/_matrix/client/v1/rooms/!foo%3Abar/relations/" +
-                    encodeURIComponent(root.event_id!) +
-                    "/" +
-                    encodeURIComponent(THREAD_RELATION_TYPE.name) +
-                    "?dir=b&limit=1",
+                "/_matrix/client/v1/rooms/!foo%3Abar/relations/" + encodeURIComponent(root.event_id!) + "?dir=b",
            );
            request.respond(200, function () {
                return {
@@ -2034,9 +2022,7 @@ describe("MatrixClient event timelines", function () {
                    "GET",
                    "/_matrix/client/v1/rooms/!foo%3Abar/relations/" +
                        encodeURIComponent(THREAD_ROOT.event_id!) +
-                        "/" +
-                        encodeURIComponent(THREAD_RELATION_TYPE.name) +
-                        buildRelationPaginationQuery({ dir: Direction.Backward, limit: 1 }),
+                        buildRelationPaginationQuery({ dir: Direction.Backward }),
                )
                .respond(200, function () {
                    return {
@@ -150,7 +150,7 @@ describe("MatrixClient", function () {
    });

    describe("joinRoom", function () {
-        it("should no-op if you've already joined a room", function () {
+        it("should no-op given the ID of a room you've already joined", async () => {
            const roomId = "!foo:bar";
            const room = new Room(roomId, client, userId);
            client.fetchRoomEvent = () =>
@@ -168,8 +168,32 @@ describe("MatrixClient", function () {
            ]);
            httpBackend.verifyNoOutstandingRequests();
            store.storeRoom(room);
-            client.joinRoom(roomId);
+
+            const joinPromise = client.joinRoom(roomId);
            httpBackend.verifyNoOutstandingRequests();
+            expect(await joinPromise).toBe(room);
+        });
+
+        it("should no-op given the alias of a room you've already joined", async () => {
+            const roomId = "!roomId:server";
+            const roomAlias = "#my-fancy-room:server";
+            const room = new Room(roomId, client, userId);
+            room.addLiveEvents([
+                utils.mkMembership({
+                    user: userId,
+                    room: roomId,
+                    mship: "join",
+                    event: true,
+                }),
+            ]);
+            store.storeRoom(room);
+
+            // The method makes a request to resolve the alias
+            httpBackend.when("POST", "/join/" + encodeURIComponent(roomAlias)).respond(200, { room_id: roomId });
+
+            const joinPromise = client.joinRoom(roomAlias);
+            await httpBackend.flushAllExpected();
+            expect(await joinPromise).toBe(room);
        });

        it("should send request to inviteSignUrl if specified", async () => {
@@ -1180,51 +1204,20 @@ describe("MatrixClient", function () {

    describe("requestLoginToken", () => {
        it("should hit the expected API endpoint with UIA", async () => {
-            httpBackend
-                .when("GET", "/capabilities")
-                .respond(200, { capabilities: { "org.matrix.msc3882.get_login_token": { enabled: true } } });
            const response = {};
            const uiaData = {};
            const prom = client.requestLoginToken(uiaData);
-            httpBackend
-                .when("POST", "/unstable/org.matrix.msc3882/login/get_token", { auth: uiaData })
-                .respond(200, response);
+            httpBackend.when("POST", "/v1/login/get_token", { auth: uiaData }).respond(200, response);
            await httpBackend.flush("");
            expect(await prom).toStrictEqual(response);
        });

        it("should hit the expected API endpoint without UIA", async () => {
-            httpBackend
-                .when("GET", "/capabilities")
-                .respond(200, { capabilities: { "org.matrix.msc3882.get_login_token": { enabled: true } } });
            const response = { login_token: "xyz", expires_in_ms: 5000 };
            const prom = client.requestLoginToken();
-            httpBackend.when("POST", "/unstable/org.matrix.msc3882/login/get_token", {}).respond(200, response);
+            httpBackend.when("POST", "/v1/login/get_token", {}).respond(200, response);
            await httpBackend.flush("");
-            // check that expires_in has been populated for compatibility with r0
-            expect(await prom).toStrictEqual({ ...response, expires_in: 5 });
-        });
-
-        it("should hit the r1 endpoint when capability is disabled", async () => {
-            httpBackend
-                .when("GET", "/capabilities")
-                .respond(200, { capabilities: { "org.matrix.msc3882.get_login_token": { enabled: false } } });
-            const response = { login_token: "xyz", expires_in_ms: 5000 };
-            const prom = client.requestLoginToken();
-            httpBackend.when("POST", "/unstable/org.matrix.msc3882/login/get_token", {}).respond(200, response);
-            await httpBackend.flush("");
-            // check that expires_in has been populated for compatibility with r0
-            expect(await prom).toStrictEqual({ ...response, expires_in: 5 });
-        });
-
-        it("should hit the r0 endpoint for fallback", async () => {
-            httpBackend.when("GET", "/capabilities").respond(200, {});
-            const response = { login_token: "xyz", expires_in: 5 };
-            const prom = client.requestLoginToken();
-            httpBackend.when("POST", "/unstable/org.matrix.msc3882/login/token", {}).respond(200, response);
-            await httpBackend.flush("");
-            // check that expires_in has been populated for compatibility with r1
-            expect(await prom).toStrictEqual({ ...response, expires_in_ms: 5000 });
+            expect(await prom).toStrictEqual(response);
        });
    });

@@ -0,0 +1,162 @@
+/*
+Copyright 2023 Holi Moli GmbH
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import "fake-indexeddb/auto";
+import fetchMock from "fetch-mock-jest";
+
+import { MatrixClient, ClientEvent, createClient, SyncState } from "../../src";
+
+const makeQueryablePromise = <T = void>(promise: Promise<T>) => {
+    let resolved = false;
+    let rejected = false;
+
+    // Observe the promise, saving the fulfillment in a closure scope.
+    const newPromise = promise.then(
+        (value) => {
+            resolved = true;
+            return value;
+        },
+        (error) => {
+            rejected = true;
+            throw error;
+        },
+    );
+    const isFulfilled = () => {
+        return resolved || rejected;
+    };
+    const isResolved = () => {
+        return resolved;
+    };
+    const isRejected = () => {
+        return rejected;
+    };
+    return { promise: newPromise, isFulfilled, isResolved, isRejected };
+};
+
+const queryablePromise = <T = void>() => {
+    let resolve!: (value: T | PromiseLike<T>) => void;
+    let reject!: (reason?: any) => void;
+
+    const promise = makeQueryablePromise<T>(
+        new Promise<T>((_resolve, _reject) => {
+            resolve = _resolve;
+            reject = _reject;
+        }),
+    );
+
+    return { resolve, reject, ...promise };
+};
+
+describe("MatrixClient syncing errors", () => {
+    const selfUserId = "@alice:localhost";
+    const selfAccessToken = "aseukfgwef";
+    const unknownTokenErrorData = {
+        status: 401,
+        body: {
+            errcode: "M_UNKNOWN_TOKEN",
+            error: "Invalid access token passed.",
+            soft_logout: false,
+        },
+    };
+    let client: MatrixClient | undefined;
+
+    beforeEach(() => {
+        client = createClient({
+            baseUrl: "http://tocal.test.server",
+            userId: selfUserId,
+            accessToken: selfAccessToken,
+            deviceId: "myDevice",
+        });
+    });
+
+    it("should retry, until errors are solved.", async () => {
+        jest.useFakeTimers();
+        fetchMock.config.overwriteRoutes = false;
+        fetchMock
+            .getOnce("end:versions", {}) // first version check without credentials needs to succeed
+            .getOnce("end:versions", 429) // second version check fails with 429 triggering another retry
+            .get("end:versions", {}) // further version checks succeed
+            .getOnce("end:pushrules/", 429) // first pushrules check fails starting retry
+            .get("end:pushrules/", {}) // further pushrules check succeed
+            .catch({}); // all other calls succeed
+
+        const syncEvents = Array.from({ length: 5 }, queryablePromise<SyncState>);
+
+        client!.on(ClientEvent.Sync, (state: SyncState, lastState: SyncState | null) => {
+            let i = 0;
+            for (; i < syncEvents.length && syncEvents[i].isFulfilled(); i++) {
+                // find index of first unfulfilled promise
+            }
+            syncEvents[i].resolve(state);
+        });
+
+        await client!.startClient();
+        expect(await syncEvents[0].promise).toBe(SyncState.Error);
+        jest.runAllTimers(); // this will skip forward to trigger the keepAlive/sync
+        expect(await syncEvents[1].promise).toBe(SyncState.Error);
+        jest.runAllTimers(); // this will skip forward to trigger the keepAlive/sync
+        expect(await syncEvents[2].promise).toBe(SyncState.Prepared);
+        jest.runAllTimers(); // this will skip forward to trigger the keepAlive/sync
+        expect(await syncEvents[3].promise).toBe(SyncState.Syncing);
+        jest.runAllTimers(); // this will skip forward to trigger the keepAlive/sync
+        expect(await syncEvents[4].promise).toBe(SyncState.Syncing);
+    });
+
+    it("should stop sync keep alive when client is stopped.", async () => {
+        jest.useFakeTimers();
+        fetchMock.config.overwriteRoutes = false;
+        fetchMock
+            .getOnce("end:versions", {}) // first version check without credentials needs to succeed
+            .get("end:versions", unknownTokenErrorData) // further version checks fails with 401
+            .get("end:pushrules/", 401) // fails with 401 without an error. This does happen in practice e.g. with Synapse
+            .post("end:logout", unknownTokenErrorData) // just to keep up a consistent scenario. Does not have a real effect for this testcase
+            .post("end:filter", 401); // just to keep up a consistent scenario. Does not have a real effect for this testcase
+
+        const firstSyncEvent = queryablePromise<SyncState>();
+        const secondSyncEvent = queryablePromise<SyncState>();
+        client!.on(ClientEvent.Sync, (state: SyncState, lastState: SyncState | null) => {
+            if (firstSyncEvent.isFulfilled()) secondSyncEvent.resolve(state);
+            firstSyncEvent.resolve(state);
+        });
+
+        await client!.startClient();
+        const logoutDone = queryablePromise();
+        client!
+            .logout(true)
+            .then(() => {
+                logoutDone.resolve();
+            })
+            .catch((e) => {
+                logoutDone.resolve();
+            });
+
+        const syntState = await firstSyncEvent.promise;
+        expect(syntState).toBe(SyncState.Error);
+        jest.runAllTimers(); // this will skip forward to trigger the keepAlive
+
+        jest.useRealTimers(); // we need real timer for the setTimout below to work
+
+        const timeoutPromise = makeQueryablePromise(new Promise<void>((res) => setTimeout(res, 1)));
+
+        await Promise.race([secondSyncEvent.promise, timeoutPromise.promise]);
+        // when syncing stopped, then the secondSyncEvent will never happen and the promise will not be resolved,
+        /// so the timeoutPromise will be resolved instead
+        expect(timeoutPromise.isFulfilled()).toBe(true);
+        expect(secondSyncEvent.isFulfilled()).toBe(false);
+
+        await logoutDone.promise; // wait for the logout to finish to prevent processing and logging after the test is done.
+    });
+});
@@ -28,32 +28,70 @@ import {
    NotificationCountType,
    RelationType,
    Room,
+    fixNotificationCountOnDecryption,
 } from "../../src";
 import { TestClient } from "../TestClient";
 import { ReceiptType } from "../../src/@types/read_receipts";
 import { mkThread } from "../test-utils/thread";
 import { SyncState } from "../../src/sync";

+const userA = "@alice:localhost";
+const userB = "@bob:localhost";
+const selfUserId = userA;
+const selfAccessToken = "aseukfgwef";
+
+function setupTestClient(): [MatrixClient, HttpBackend] {
+    const testClient = new TestClient(selfUserId, "DEVICE", selfAccessToken);
+    const httpBackend = testClient.httpBackend;
+    const client = testClient.client;
+    httpBackend!.when("GET", "/versions").respond(200, {});
+    httpBackend!.when("GET", "/pushrules").respond(200, {});
+    httpBackend!.when("POST", "/filter").respond(200, { filter_id: "a filter id" });
+    return [client, httpBackend];
+}
+
+describe("Notification count fixing", () => {
+    let client: MatrixClient | undefined;
+
+    beforeEach(() => {
+        [client] = setupTestClient();
+    });
+
+    it("doesn't increment notification count for events that can't be found in a room", async () => {
+        const roomId = "!room:localhost";
+
+        client!.startClient({ threadSupport: true });
+        const room = new Room(roomId, client!, selfUserId);
+        jest.spyOn(client!, "getRoom").mockImplementation((id) => (id === roomId ? room : null));
+
+        const event = new MatrixEvent({
+            room_id: roomId,
+            type: "m.reaction",
+            event_id: "$foo",
+            content: {
+                "m.relates_to": {
+                    rel_type: RelationType.Annotation,
+                    event_id: "$foo",
+                    key: "x",
+                },
+            },
+        });
+
+        jest.spyOn(event, "getPushActions").mockReturnValue({
+            notify: true,
+            tweaks: {},
+        });
+
+        fixNotificationCountOnDecryption(client!, event);
+
+        expect(room.getUnreadNotificationCount(NotificationCountType.Total)).toBe(0);
+    });
+});
+
 describe("MatrixClient syncing", () => {
-    const userA = "@alice:localhost";
-    const userB = "@bob:localhost";
-
-    const selfUserId = userA;
-    const selfAccessToken = "aseukfgwef";
-
    let client: MatrixClient | undefined;
    let httpBackend: HttpBackend | undefined;

-    const setupTestClient = (): [MatrixClient, HttpBackend] => {
-        const testClient = new TestClient(selfUserId, "DEVICE", selfAccessToken);
-        const httpBackend = testClient.httpBackend;
-        const client = testClient.client;
-        httpBackend!.when("GET", "/versions").respond(200, {});
-        httpBackend!.when("GET", "/pushrules").respond(200, {});
-        httpBackend!.when("POST", "/filter").respond(200, { filter_id: "a filter id" });
-        return [client, httpBackend];
-    };
-
    beforeEach(() => {
        [client, httpBackend] = setupTestClient();
    });
@@ -20,7 +20,7 @@ import { logger } from "../src/logger";
 // try to load the olm library.
 try {
    // eslint-disable-next-line @typescript-eslint/no-var-requires
-    global.Olm = require("@matrix-org/olm");
+    globalThis.Olm = require("@matrix-org/olm");
    logger.log("loaded libolm");
 } catch (e) {
    logger.warn("unable to run crypto tests: libolm not available", e);
@@ -0,0 +1,108 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import fetchMock from "fetch-mock-jest";
+import { MockOptionsMethodPut } from "fetch-mock";
+
+import { ISyncResponder } from "./SyncResponder";
+
+/**
+ *  An object which intercepts `account_data` get and set requests via fetch-mock.
+ */
+export class AccountDataAccumulator {
+    /**
+     * The account data events to be returned by the sync.
+     * Will be updated when fetchMock intercepts calls to PUT `/_matrix/client/v3/user/:userId/account_data/`.
+     * Will be used by `sendSyncResponseWithUpdatedAccountData`
+     */
+    public accountDataEvents: Map<String, any> = new Map();
+
+    /**
+     * Intercept requests to set a particular type of account data.
+     *
+     * Once it is set, its data is stored (for future return by `interceptGetAccountData` etc) and the resolved promise is
+     * resolved.
+     *
+     * @param accountDataType - type of account data to be intercepted
+     * @param opts - options to pass to fetchMock
+     * @returns a Promise which will resolve (with the content of the account data) once it is set.
+     */
+    public interceptSetAccountData(accountDataType: string, opts?: MockOptionsMethodPut): Promise<any> {
+        return new Promise((resolve) => {
+            // Called when the cross signing key is uploaded
+            fetchMock.put(
+                `express:/_matrix/client/v3/user/:userId/account_data/${accountDataType}`,
+                (url: string, options: RequestInit) => {
+                    const content = JSON.parse(options.body as string);
+                    const type = url.split("/").pop();
+                    // update account data for sync response
+                    this.accountDataEvents.set(type!, content);
+                    resolve(content);
+                    return {};
+                },
+                opts,
+            );
+        });
+    }
+
+    /**
+     * Intercept all requests to get account data
+     */
+    public interceptGetAccountData(): void {
+        fetchMock.get(
+            `express:/_matrix/client/v3/user/:userId/account_data/:type`,
+            (url) => {
+                const type = url.split("/").pop();
+                const existing = this.accountDataEvents.get(type!);
+                if (existing) {
+                    // return it
+                    return {
+                        status: 200,
+                        body: existing,
+                    };
+                } else {
+                    // 404
+                    return {
+                        status: 404,
+                        body: { errcode: "M_NOT_FOUND", error: "Account data not found." },
+                    };
+                }
+            },
+            { overwriteRoutes: true },
+        );
+    }
+
+    /**
+     * Send a sync response the current account data events.
+     */
+    public sendSyncResponseWithUpdatedAccountData(syncResponder: ISyncResponder): void {
+        try {
+            syncResponder.sendOrQueueSyncResponse({
+                next_batch: 1,
+                account_data: {
+                    events: Array.from(this.accountDataEvents, ([type, content]) => ({
+                        type: type,
+                        content: content,
+                    })),
+                },
+            });
+        } catch (err) {
+            // Might fail with "Cannot queue more than one /sync response" if called too often.
+            // It's ok if it fails here, the sync response is cumulative and will contain
+            // the latest account data.
+        }
+    }
+}
@@ -315,6 +315,7 @@ export interface IMessageOpts {
    event?: boolean;
    relatesTo?: IEventRelation;
    ts?: number;
+    unsigned?: IUnsigned;
 }

 /**
@@ -537,8 +538,6 @@ export async function awaitDecryption(
    });
 }

-export const emitPromise = (e: EventEmitter, k: string): Promise<any> => new Promise((r) => e.once(k, r));
-
 export const mkPusher = (extra: Partial<IPusher> = {}): IPusher => ({
    app_display_name: "app",
    app_id: "123",
@@ -561,3 +560,25 @@ CRYPTO_BACKENDS["rust-sdk"] = (client: MatrixClient) => client.initRustCrypto();
 if (global.Olm) {
    CRYPTO_BACKENDS["libolm"] = (client: MatrixClient) => client.initCrypto();
 }
+
+export const emitPromise = (e: EventEmitter, k: string): Promise<any> => new Promise((r) => e.once(k, r));
+
+/**
+ * Advance the fake timers in a loop until the given promise resolves or rejects.
+ *
+ * Returns the result of the promise.
+ *
+ * This can be useful when there are multiple steps in the code which require an iteration of the event loop.
+ */
+export async function advanceTimersUntil<T>(promise: Promise<T>): Promise<T> {
+    let resolved = false;
+    promise.finally(() => {
+        resolved = true;
+    });
+
+    while (!resolved) {
+        await jest.advanceTimersByTimeAsync(1);
+    }
+
+    return await promise;
+}
@@ -161,3 +161,23 @@ export const mkThread = ({

    return { thread, rootEvent, events };
 };
+
+/**
+ * Create a thread, and make sure the events are added to the thread and the
+ * room's timeline as if they came in via sync.
+ *
+ * Note that mkThread doesn't actually add the events properly to the room.
+ */
+export const populateThread = ({
+    room,
+    client,
+    authorId,
+    participantUserIds,
+    length = 2,
+    ts = 1,
+}: MakeThreadProps): MakeThreadResult => {
+    const ret = mkThread({ room, client, authorId, participantUserIds, length, ts });
+    ret.thread.initialEventsFetched = true;
+    room.addLiveEvents(ret.events);
+    return ret;
+};
@@ -269,7 +269,11 @@ export class MockRTCRtpTransceiver {
 }

 export class MockMediaStreamTrack {
-    constructor(public readonly id: string, public readonly kind: "audio" | "video", public enabled = true) {}
+    constructor(
+        public readonly id: string,
+        public readonly kind: "audio" | "video",
+        public enabled = true,
+    ) {}

    public stop = jest.fn<void, []>();

@@ -306,7 +310,10 @@ export class MockMediaStreamTrack {
 // XXX: Using EventTarget in jest doesn't seem to work, so we write our own
 // implementation
 export class MockMediaStream {
-    constructor(public id: string, private tracks: MockMediaStreamTrack[] = []) {}
+    constructor(
+        public id: string,
+        private tracks: MockMediaStreamTrack[] = [],
+    ) {}

    public listeners: [string, (...args: any[]) => any][] = [];
    public isStopped = false;
@@ -435,7 +442,11 @@ type EmittedEventMap = CallEventHandlerEventHandlerMap &
 export class MockCallMatrixClient extends TypedEventEmitter<EmittedEvents, EmittedEventMap> {
    public mediaHandler = new MockMediaHandler();

-    constructor(public userId: string, public deviceId: string, public sessionId: string) {
+    constructor(
+        public userId: string,
+        public deviceId: string,
+        public sessionId: string,
+    ) {
        super();
    }

@@ -502,7 +513,10 @@ export class MockCallMatrixClient extends TypedEventEmitter<EmittedEvents, Emitt
 }

 export class MockMatrixCall extends TypedEventEmitter<CallEvent, CallEventHandlerMap> {
-    constructor(public roomId: string, public groupCallId?: string) {
+    constructor(
+        public roomId: string,
+        public groupCallId?: string,
+    ) {
        super();
    }

@@ -550,7 +564,11 @@ export class MockMatrixCall extends TypedEventEmitter<CallEvent, CallEventHandle
 }

 export class MockCallFeed {
-    constructor(public userId: string, public deviceId: string | undefined, public stream: MockMediaStream) {}
+    constructor(
+        public userId: string,
+        public deviceId: string | undefined,
+        public stream: MockMediaStream,
+    ) {}

    public measureVolumeActivity(val: boolean) {}
    public dispose() {}
@@ -351,7 +351,7 @@ describe("AutoDiscovery", function () {
        function () {
            const httpBackend = getHttpBackend();
            httpBackend.when("GET", "/_matrix/client/versions").respond(200, {
-                not_matrix_versions: ["v1.1"],
+                not_matrix_versions: ["v1.5"],
            });
            httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
                "m.homeserver": {
@@ -388,7 +388,7 @@ describe("AutoDiscovery", function () {
                expect(req.path).toEqual("https://example.org/_matrix/client/versions");
            })
            .respond(200, {
-                versions: ["v1.1"],
+                versions: ["v1.5"],
            });
        httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
            "m.homeserver": {
@@ -428,7 +428,7 @@ describe("AutoDiscovery", function () {
                expect(req.path).toEqual("https://chat.example.org/_matrix/client/versions");
            })
            .respond(200, {
-                versions: ["v1.1"],
+                versions: ["v1.5"],
            });
        httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
            "m.homeserver": {
@@ -469,7 +469,7 @@ describe("AutoDiscovery", function () {
                expect(req.path).toEqual("https://chat.example.org/_matrix/client/versions");
            })
            .respond(200, {
-                versions: ["v1.1"],
+                versions: ["v1.5"],
            });
        httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
            "m.homeserver": {
@@ -515,7 +515,7 @@ describe("AutoDiscovery", function () {
                    expect(req.path).toEqual("https://chat.example.org/_matrix/client/versions");
                })
                .respond(200, {
-                    versions: ["v1.1"],
+                    versions: ["v1.5"],
                });
            httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
                "m.homeserver": {
@@ -560,7 +560,7 @@ describe("AutoDiscovery", function () {
                    expect(req.path).toEqual("https://chat.example.org/_matrix/client/versions");
                })
                .respond(200, {
-                    versions: ["v1.1"],
+                    versions: ["v1.5"],
                });
            httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
                "m.homeserver": {
@@ -606,7 +606,7 @@ describe("AutoDiscovery", function () {
                    expect(req.path).toEqual("https://chat.example.org/_matrix/client/versions");
                })
                .respond(200, {
-                    versions: ["v1.1"],
+                    versions: ["v1.5"],
                });
            httpBackend.when("GET", "/_matrix/identity/v2").respond(404, {});
            httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
@@ -653,7 +653,7 @@ describe("AutoDiscovery", function () {
                    expect(req.path).toEqual("https://chat.example.org/_matrix/client/versions");
                })
                .respond(200, {
-                    versions: ["v1.1"],
+                    versions: ["v1.5"],
                });
            httpBackend.when("GET", "/_matrix/identity/v2").respond(500, {});
            httpBackend.when("GET", "/.well-known/matrix/client").respond(200, {
@@ -697,7 +697,7 @@ describe("AutoDiscovery", function () {
                expect(req.path).toEqual("https://chat.example.org/_matrix/client/versions");
            })
            .respond(200, {
-                versions: ["v1.1"],
+                versions: ["v1.5"],
            });
        httpBackend
            .when("GET", "/_matrix/identity/v2")
@@ -747,7 +747,7 @@ describe("AutoDiscovery", function () {
                expect(req.path).toEqual("https://chat.example.org/_matrix/client/versions");
            })
            .respond(200, {
-                versions: ["v1.1"],
+                versions: ["v1.5"],
            });
        httpBackend
            .when("GET", "/_matrix/identity/v2")
@@ -910,7 +910,7 @@ describe("AutoDiscovery", function () {

        beforeEach(() => {
            fetchMock.resetBehavior();
-            fetchMock.get(`${homeserverUrl}_matrix/client/versions`, { versions: ["v1.1"] });
+            fetchMock.get(`${homeserverUrl}_matrix/client/versions`, { versions: ["v1.5"] });

            fetchMock.get("https://example.org/.well-known/matrix/client", {
                "m.homeserver": {
@@ -0,0 +1,88 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { TextEncoder, TextDecoder } from "util";
+import NodeBuffer from "node:buffer";
+
+import { decodeBase64, encodeBase64, encodeUnpaddedBase64, encodeUnpaddedBase64Url } from "../../src/base64";
+
+describe.each(["browser", "node"])("Base64 encoding (%s)", (env) => {
+    let origBuffer = Buffer;
+
+    beforeAll(() => {
+        if (env === "browser") {
+            origBuffer = Buffer;
+            // @ts-ignore
+            // eslint-disable-next-line no-global-assign
+            Buffer = undefined;
+
+            global.atob = NodeBuffer.atob;
+            global.btoa = NodeBuffer.btoa;
+        }
+    });
+
+    afterAll(() => {
+        // eslint-disable-next-line no-global-assign
+        Buffer = origBuffer;
+        // @ts-ignore
+        global.atob = undefined;
+        // @ts-ignore
+        global.btoa = undefined;
+    });
+
+    it("Should decode properly encoded data", () => {
+        const decoded = new TextDecoder().decode(decodeBase64("ZW5jb2RpbmcgaGVsbG8gd29ybGQ="));
+
+        expect(decoded).toStrictEqual("encoding hello world");
+    });
+
+    it("Should encode unpadded URL-safe base64", () => {
+        const toEncode = "?????";
+        const data = new TextEncoder().encode(toEncode);
+
+        const encoded = encodeUnpaddedBase64Url(data);
+        expect(encoded).toEqual("Pz8_Pz8");
+    });
+
+    it("Should decode URL-safe base64", () => {
+        const decoded = new TextDecoder().decode(decodeBase64("Pz8_Pz8="));
+
+        expect(decoded).toStrictEqual("?????");
+    });
+
+    it("Encode unpadded should not have padding", () => {
+        const toEncode = "encoding hello world";
+        const data = new TextEncoder().encode(toEncode);
+
+        const paddedEncoded = encodeBase64(data);
+        const unpaddedEncoded = encodeUnpaddedBase64(data);
+
+        expect(paddedEncoded).not.toEqual(unpaddedEncoded);
+
+        const padding = paddedEncoded.charAt(paddedEncoded.length - 1);
+        expect(padding).toStrictEqual("=");
+    });
+
+    it("Decode should be indifferent to padding", () => {
+        const withPadding = "ZW5jb2RpbmcgaGVsbG8gd29ybGQ=";
+        const withoutPadding = "ZW5jb2RpbmcgaGVsbG8gd29ybGQ";
+
+        const decodedPad = decodeBase64(withPadding);
+        const decodedNoPad = decodeBase64(withoutPadding);
+
+        expect(decodedPad).toStrictEqual(decodedNoPad);
+    });
+});
@@ -115,6 +115,16 @@ describe("Crypto", function () {
        expect(Crypto.getOlmVersion()[0]).toEqual(3);
    });

+    it("getVersion() should return the current version of the olm library", async () => {
+        const client = new TestClient("@alice:example.com", "deviceid").client;
+        await client.initCrypto();
+
+        const olmVersionTuple = Crypto.getOlmVersion();
+        expect(client.getCrypto()?.getVersion()).toBe(
+            `Olm ${olmVersionTuple[0]}.${olmVersionTuple[1]}.${olmVersionTuple[2]}`,
+        );
+    });
+
    describe("encrypted events", function () {
        it("provides encryption information for events from unverified senders", async function () {
            const client = new TestClient("@alice:example.com", "deviceid").client;
@@ -258,7 +268,7 @@ describe("Crypto", function () {
                const event = await buildEncryptedEvent();
                expect(await client.getCrypto()!.getEncryptionInfoForEvent(event)).toEqual({
                    shieldColour: EventShieldColour.RED,
-                    shieldReason: EventShieldReason.UNVERIFIED_IDENTITY,
+                    shieldReason: EventShieldReason.UNSIGNED_DEVICE,
                });
            });

@@ -346,7 +356,6 @@ describe("Crypto", function () {

        let crypto: Crypto;
        let mockBaseApis: MatrixClient;
-        let mockRoomList: RoomList;

        let fakeEmitter: EventEmitter;

@@ -380,19 +389,10 @@ describe("Crypto", function () {
                isGuest: jest.fn(),
                emit: jest.fn(),
            } as unknown as MatrixClient;
-            mockRoomList = {} as unknown as RoomList;

            fakeEmitter = new EventEmitter();

-            crypto = new Crypto(
-                mockBaseApis,
-                "@alice:home.server",
-                "FLIBBLE",
-                clientStore,
-                cryptoStore,
-                mockRoomList,
-                [],
-            );
+            crypto = new Crypto(mockBaseApis, "@alice:home.server", "FLIBBLE", clientStore, cryptoStore, []);
            crypto.registerEventHandlers(fakeEmitter as any);
            await crypto.init();
        });
@@ -1106,7 +1106,7 @@ describe("Crypto", function () {

    describe("Secret storage", function () {
        it("creates secret storage even if there is no keyInfo", async function () {
-            jest.spyOn(logger, "log").mockImplementation(() => {});
+            jest.spyOn(logger, "debug").mockImplementation(() => {});
            jest.setTimeout(10000);
            const client = new TestClient("@a:example.com", "dev").client;
            await client.initCrypto();
@@ -1263,7 +1263,7 @@ describe("Crypto", function () {
                    ({
                        init_with_private_key: jest.fn(),
                        free,
-                    } as unknown as PkDecryption),
+                    }) as unknown as PkDecryption,
            );
            client.client.checkSecretStoragePrivateKey(new Uint8Array(), "");
            expect(free).toHaveBeenCalled();
@@ -1289,7 +1289,7 @@ describe("Crypto", function () {
                    ({
                        init_with_seed: jest.fn(),
                        free,
-                    } as unknown as PkSigning),
+                    }) as unknown as PkSigning,
            );
            client.client.checkCrossSigningPrivateKey(new Uint8Array(), "");
            expect(free).toHaveBeenCalled();
@@ -1331,15 +1331,9 @@ describe("Crypto", function () {
                setRoomEncryption: jest.fn().mockResolvedValue(undefined),
            } as unknown as RoomList;

-            crypto = new Crypto(
-                mockClient,
-                "@alice:home.server",
-                "FLIBBLE",
-                clientStore,
-                cryptoStore,
-                mockRoomList,
-                [],
-            );
+            crypto = new Crypto(mockClient, "@alice:home.server", "FLIBBLE", clientStore, cryptoStore, []);
+            // @ts-ignore we are injecting a mock into a private property
+            crypto.roomList = mockRoomList;
        });

        it("should set the algorithm if called for a known room", async () => {
@@ -215,6 +215,36 @@ describe("MegolmBackup", function () {
            jest.spyOn(global, "setTimeout").mockRestore();
        });

+        test("fail if crypto not enabled", async () => {
+            const client = makeTestClient(cryptoStore);
+            const data = {
+                algorithm: olmlib.MEGOLM_BACKUP_ALGORITHM,
+                version: "1",
+                auth_data: {
+                    public_key: "hSDwCYkwp1R0i33ctD73Wg2/Og0mOBr066SpjqqbTmo",
+                },
+            };
+            await expect(client.restoreKeyBackupWithSecretStorage(data)).rejects.toThrow(
+                "End-to-end encryption disabled",
+            );
+        });
+
+        test("fail if given backup has no version", async () => {
+            const client = makeTestClient(cryptoStore);
+            await client.initCrypto();
+            const data = {
+                algorithm: olmlib.MEGOLM_BACKUP_ALGORITHM,
+                auth_data: {
+                    public_key: "hSDwCYkwp1R0i33ctD73Wg2/Og0mOBr066SpjqqbTmo",
+                },
+            };
+            const key = Uint8Array.from([1, 2, 3, 4, 5, 6, 7, 8]);
+            await client.getCrypto()!.storeSessionBackupPrivateKey(key, "1");
+            await expect(client.restoreKeyBackupWithCache(undefined, undefined, data)).rejects.toThrow(
+                "Backup version must be defined",
+            );
+        });
+
        it("automatically calls the key back up", function () {
            const groupSession = new Olm.OutboundGroupSession();
            groupSession.create();
@@ -1,52 +0,0 @@
-/*
-Copyright 2023 The Matrix.org Foundation C.I.C.
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-*/
-
-import { TextEncoder, TextDecoder } from "util";
-
-import { decodeBase64, encodeBase64, encodeUnpaddedBase64 } from "../../../src/common-crypto/base64";
-
-describe("Crypto Base64 encoding", () => {
-    it("Should decode properly encoded data", async () => {
-        const toEncode = "encoding hello world";
-        const encoded = encodeBase64(new TextEncoder().encode(toEncode));
-        const decoded = new TextDecoder().decode(decodeBase64(encoded));
-
-        expect(decoded).toStrictEqual(toEncode);
-    });
-
-    it("Encode unpadded should not have padding", async () => {
-        const toEncode = "encoding hello world";
-        const data = new TextEncoder().encode(toEncode);
-
-        const paddedEncoded = encodeBase64(data);
-        const unpaddedEncoded = encodeUnpaddedBase64(data);
-
-        expect(paddedEncoded).not.toEqual(unpaddedEncoded);
-
-        const padding = paddedEncoded.charAt(paddedEncoded.length - 1);
-        expect(padding).toStrictEqual("=");
-    });
-
-    it("Decode should be indifferent to padding", async () => {
-        const withPadding = "ZW5jb2RpbmcgaGVsbG8gd29ybGQ=";
-        const withoutPadding = "ZW5jb2RpbmcgaGVsbG8gd29ybGQ";
-
-        const decodedPad = decodeBase64(withPadding);
-        const decodedNoPad = decodeBase64(withoutPadding);
-
-        expect(decodedPad).toStrictEqual(decodedNoPad);
-    });
-});
@@ -106,7 +106,7 @@ describe("Cross Signing", function () {
        });
        alice.uploadKeySignatures = async () => ({ failures: {} });
        alice.setAccountData = async () => ({});
-        alice.getAccountDataFromServer = async <T>() => ({} as T);
+        alice.getAccountDataFromServer = async <T>() => ({}) as T;
        // set Alice's cross-signing key
        await alice.bootstrapCrossSigning({
            authUploadDeviceSigningKeys: async (func) => {
@@ -146,7 +146,7 @@ describe("Cross Signing", function () {
        };
        alice.uploadKeySignatures = async () => ({ failures: {} });
        alice.setAccountData = async () => ({});
-        alice.getAccountDataFromServer = async <T extends { [k: string]: any }>(): Promise<T | null> => ({} as T);
+        alice.getAccountDataFromServer = async <T extends { [k: string]: any }>(): Promise<T | null> => ({}) as T;
        const authUploadDeviceSigningKeys: BootstrapCrossSigningOpts["authUploadDeviceSigningKeys"] = async (func) => {
            await func({});
        };
@@ -33,12 +33,10 @@ export async function resetCrossSigningKeys(

 export async function createSecretStorageKey(): Promise<IRecoveryKey> {
    const decryption = new global.Olm.PkDecryption();
-    const storagePublicKey = decryption.generate_key();
+    decryption.generate_key();
    const storagePrivateKey = decryption.get_private_key();
    decryption.free();
    return {
-        // `pubkey` not used anymore with symmetric 4S
-        keyInfo: { pubkey: storagePublicKey, key: undefined! },
        privateKey: storagePrivateKey,
    };
 }
@@ -28,6 +28,7 @@ import { DeviceInfo } from "../../../src/crypto/deviceinfo";
 import { ISignatures } from "../../../src/@types/signed";
 import { ICurve25519AuthData } from "../../../src/crypto/keybackup";
 import { SecretStorageKeyDescription, SECRET_STORAGE_ALGORITHM_V1_AES } from "../../../src/secret-storage";
+import { decodeBase64 } from "../../../src/base64";

 async function makeTestClient(
    userInfo: { userId: string; deviceId: string },
@@ -189,10 +190,7 @@ describe("Secrets", function () {
        };
        resetCrossSigningKeys(alice);

-        const { keyId: newKeyId } = await alice.addSecretStorageKey(SECRET_STORAGE_ALGORITHM_V1_AES, {
-            pubkey: undefined,
-            key: undefined,
-        });
+        const { keyId: newKeyId } = await alice.addSecretStorageKey(SECRET_STORAGE_ALGORITHM_V1_AES, { key });
        // we don't await on this because it waits for the event to come down the sync
        // which won't happen in the test setup
        alice.setDefaultSecretStorageKeyId(newKeyId);
@@ -275,13 +273,13 @@ describe("Secrets", function () {

    describe("bootstrap", function () {
        // keys used in some of the tests
-        const XSK = new Uint8Array(olmlib.decodeBase64("3lo2YdJugHjfE+Or7KJ47NuKbhE7AAGLgQ/dc19913Q="));
+        const XSK = new Uint8Array(decodeBase64("3lo2YdJugHjfE+Or7KJ47NuKbhE7AAGLgQ/dc19913Q="));
        const XSPubKey = "DRb8pFVJyEJ9OWvXeUoM0jq/C2Wt+NxzBZVuk2nRb+0";
-        const USK = new Uint8Array(olmlib.decodeBase64("lKWi3hJGUie5xxHgySoz8PHFnZv6wvNaud/p2shN9VU="));
+        const USK = new Uint8Array(decodeBase64("lKWi3hJGUie5xxHgySoz8PHFnZv6wvNaud/p2shN9VU="));
        const USPubKey = "CUpoiTtHiyXpUmd+3ohb7JVxAlUaOG1NYs9Jlx8soQU";
-        const SSK = new Uint8Array(olmlib.decodeBase64("1R6JVlXX99UcfUZzKuCDGQgJTw8ur1/ofgPD8pp+96M="));
+        const SSK = new Uint8Array(decodeBase64("1R6JVlXX99UcfUZzKuCDGQgJTw8ur1/ofgPD8pp+96M="));
        const SSPubKey = "0DfNsRDzEvkCLA0gD3m7VAGJ5VClhjEsewI35xq873Q";
-        const SSSSKey = new Uint8Array(olmlib.decodeBase64("XrmITOOdBhw6yY5Bh7trb/bgp1FRdIGyCUxxMP873R0="));
+        const SSSSKey = new Uint8Array(decodeBase64("XrmITOOdBhw6yY5Bh7trb/bgp1FRdIGyCUxxMP873R0="));

        it("bootstraps when no storage or cross-signing keys locally", async function () {
            const key = new Uint8Array(16);
@@ -334,7 +332,6 @@ describe("Secrets", function () {

        it("bootstraps when cross-signing keys in secret storage", async function () {
            const decryption = new global.Olm.PkDecryption();
-            const storagePublicKey = decryption.generate_key();
            const storagePrivateKey = decryption.get_private_key();

            const bob: MatrixClient = await makeTestClient(
@@ -377,8 +374,6 @@ describe("Secrets", function () {
            });
            await bob.bootstrapSecretStorage({
                createSecretStorageKey: async () => ({
-                    // `pubkey` not used anymore with symmetric 4S
-                    keyInfo: { pubkey: storagePublicKey },
                    privateKey: storagePrivateKey,
                }),
            });
@@ -0,0 +1,210 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import "fake-indexeddb/auto";
+import "jest-localstorage-mock";
+import { IndexedDBCryptoStore, LocalStorageCryptoStore, MemoryCryptoStore } from "../../../../src";
+import { CryptoStore, MigrationState, SESSION_BATCH_SIZE } from "../../../../src/crypto/store/base";
+
+describe.each([
+    ["IndexedDBCryptoStore", () => new IndexedDBCryptoStore(global.indexedDB, "tests")],
+    ["LocalStorageCryptoStore", () => new LocalStorageCryptoStore(localStorage)],
+    ["MemoryCryptoStore", () => new MemoryCryptoStore()],
+])("CryptoStore tests for %s", function (name, dbFactory) {
+    let store: CryptoStore;
+
+    beforeEach(async () => {
+        store = dbFactory();
+    });
+
+    describe("containsData", () => {
+        it("returns false at first", async () => {
+            expect(await store.containsData()).toBe(false);
+        });
+
+        it("returns true after startup and account setup", async () => {
+            await store.startup();
+            await store.doTxn("readwrite", [IndexedDBCryptoStore.STORE_ACCOUNT], (txn) => {
+                store.storeAccount(txn, "not a real account");
+            });
+            expect(await store.containsData()).toBe(true);
+        });
+    });
+
+    describe("migrationState", () => {
+        beforeEach(async () => {
+            await store.startup();
+        });
+
+        it("returns 0 at first", async () => {
+            expect(await store.getMigrationState()).toEqual(MigrationState.NOT_STARTED);
+        });
+
+        it("stores updates", async () => {
+            await store.setMigrationState(MigrationState.INITIAL_DATA_MIGRATED);
+            expect(await store.getMigrationState()).toEqual(MigrationState.INITIAL_DATA_MIGRATED);
+        });
+    });
+
+    describe("get/delete EndToEndSessionsBatch", () => {
+        beforeEach(async () => {
+            await store.startup();
+        });
+
+        it("returns null at first", async () => {
+            expect(await store.getEndToEndSessionsBatch()).toBe(null);
+        });
+
+        it("returns a batch of sessions", async () => {
+            // First store some sessions in the db
+            const N_DEVICES = 6;
+            const N_SESSIONS_PER_DEVICE = 6;
+            await createSessions(N_DEVICES, N_SESSIONS_PER_DEVICE);
+
+            // Then, get a batch and check it looks right.
+            const batch = await store.getEndToEndSessionsBatch();
+            expect(batch!.length).toEqual(N_DEVICES * N_SESSIONS_PER_DEVICE);
+            for (let i = 0; i < N_DEVICES; i++) {
+                for (let j = 0; j < N_SESSIONS_PER_DEVICE; j++) {
+                    const r = batch![i * N_DEVICES + j];
+
+                    expect(r.deviceKey).toEqual(`device${i}`);
+                    expect(r.sessionId).toEqual(`session${j}`);
+                }
+            }
+        });
+
+        it("returns another batch of sessions after the first batch is deleted", async () => {
+            // First store some sessions in the db
+            const N_DEVICES = 8;
+            const N_SESSIONS_PER_DEVICE = 8;
+            await createSessions(N_DEVICES, N_SESSIONS_PER_DEVICE);
+
+            // Get the first batch
+            const batch = (await store.getEndToEndSessionsBatch())!;
+            expect(batch.length).toEqual(SESSION_BATCH_SIZE);
+
+            // ... and delete.
+            await store.deleteEndToEndSessionsBatch(batch);
+
+            // Fetch a second batch
+            const batch2 = (await store.getEndToEndSessionsBatch())!;
+            expect(batch2.length).toEqual(N_DEVICES * N_SESSIONS_PER_DEVICE - SESSION_BATCH_SIZE);
+
+            // ... and delete.
+            await store.deleteEndToEndSessionsBatch(batch2);
+
+            // the batch should now be null.
+            expect(await store.getEndToEndSessionsBatch()).toBe(null);
+        });
+
+        /** Create a bunch of fake Olm sessions and stash them in the DB. */
+        async function createSessions(nDevices: number, nSessionsPerDevice: number) {
+            await store.doTxn("readwrite", IndexedDBCryptoStore.STORE_SESSIONS, (txn) => {
+                for (let i = 0; i < nDevices; i++) {
+                    for (let j = 0; j < nSessionsPerDevice; j++) {
+                        store.storeEndToEndSession(
+                            `device${i}`,
+                            `session${j}`,
+                            {
+                                deviceKey: `device${i}`,
+                                sessionId: `session${j}`,
+                            },
+                            txn,
+                        );
+                    }
+                }
+            });
+        }
+    });
+
+    describe("get/delete EndToEndInboundGroupSessionsBatch", () => {
+        beforeEach(async () => {
+            await store.startup();
+        });
+
+        it("returns null at first", async () => {
+            expect(await store.getEndToEndInboundGroupSessionsBatch()).toBe(null);
+        });
+
+        it("returns a batch of sessions", async () => {
+            const N_DEVICES = 6;
+            const N_SESSIONS_PER_DEVICE = 6;
+            await createSessions(N_DEVICES, N_SESSIONS_PER_DEVICE);
+
+            const batch = await store.getEndToEndInboundGroupSessionsBatch();
+            expect(batch!.length).toEqual(N_DEVICES * N_SESSIONS_PER_DEVICE);
+            for (let i = 0; i < N_DEVICES; i++) {
+                for (let j = 0; j < N_SESSIONS_PER_DEVICE; j++) {
+                    const r = batch![i * N_DEVICES + j];
+
+                    expect(r.senderKey).toEqual(pad43(`device${i}`));
+                    expect(r.sessionId).toEqual(`session${j}`);
+                }
+            }
+        });
+
+        it("returns another batch of sessions after the first batch is deleted", async () => {
+            // First store some sessions in the db
+            const N_DEVICES = 8;
+            const N_SESSIONS_PER_DEVICE = 8;
+            await createSessions(N_DEVICES, N_SESSIONS_PER_DEVICE);
+
+            // Get the first batch
+            const batch = (await store.getEndToEndInboundGroupSessionsBatch())!;
+            expect(batch.length).toEqual(SESSION_BATCH_SIZE);
+
+            // ... and delete.
+            await store.deleteEndToEndInboundGroupSessionsBatch(batch);
+
+            // Fetch a second batch
+            const batch2 = (await store.getEndToEndInboundGroupSessionsBatch())!;
+            expect(batch2.length).toEqual(N_DEVICES * N_SESSIONS_PER_DEVICE - SESSION_BATCH_SIZE);
+
+            // ... and delete.
+            await store.deleteEndToEndInboundGroupSessionsBatch(batch2);
+
+            // the batch should now be null.
+            expect(await store.getEndToEndInboundGroupSessionsBatch()).toBe(null);
+        });
+
+        /** Create a bunch of fake megolm sessions and stash them in the DB. */
+        async function createSessions(nDevices: number, nSessionsPerDevice: number) {
+            await store.doTxn("readwrite", IndexedDBCryptoStore.STORE_INBOUND_GROUP_SESSIONS, (txn) => {
+                for (let i = 0; i < nDevices; i++) {
+                    for (let j = 0; j < nSessionsPerDevice; j++) {
+                        store.storeEndToEndInboundGroupSession(
+                            pad43(`device${i}`),
+                            `session${j}`,
+                            {
+                                forwardingCurve25519KeyChain: [],
+                                keysClaimed: {},
+                                room_id: "",
+                                session: "",
+                            },
+                            txn,
+                        );
+                    }
+                }
+            });
+        }
+    });
+});
+
+/** Pad a string to 43 characters long */
+function pad43(x: string): string {
+    return x + ".".repeat(43 - x.length);
+}
@@ -189,12 +189,10 @@ describe("SAS verification", function () {
            const origSendToDevice = bob.client.sendToDevice.bind(bob.client);
            bob.client.sendToDevice = async (type, map) => {
                if (type === "m.key.verification.accept") {
-                    macMethod = map
-                        .get(alice.client.getUserId()!)
-                        ?.get(alice.client.deviceId!)?.message_authentication_code;
-                    keyAgreement = map
-                        .get(alice.client.getUserId()!)
-                        ?.get(alice.client.deviceId!)?.key_agreement_protocol;
+                    macMethod = map.get(alice.client.getUserId()!)?.get(alice.client.deviceId!)
+                        ?.message_authentication_code;
+                    keyAgreement = map.get(alice.client.getUserId()!)?.get(alice.client.deviceId!)
+                        ?.key_agreement_protocol;
                }
                return origSendToDevice(type, map);
            };
@@ -16,7 +16,7 @@ limitations under the License.

 import "../../../olm-loader";
 import { MatrixClient, MatrixEvent } from "../../../../src/matrix";
-import { encodeBase64 } from "../../../../src/crypto/olmlib";
+import { encodeBase64 } from "../../../../src/base64";
 import "../../../../src/crypto"; // import this to cycle-break
 import { CrossSigningInfo } from "../../../../src/crypto/CrossSigning";
 import { VerificationRequest } from "../../../../src/crypto/verification/request/VerificationRequest";
@@ -34,6 +34,7 @@ describe("eventMapperFor", function () {
                getRoom(roomId: string): Room | null {
                    return rooms.find((r) => r.roomId === roomId) ?? null;
                },
+                setUserCreator(_) {},
            } as IStore,
            scheduler: {
                setProcessFunction: jest.fn(),
@@ -14,14 +14,22 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

-import { mocked } from "jest-mock";
+import { Mocked } from "jest-mock";

 import { FetchHttpApi } from "../../../src/http-api/fetch";
 import { TypedEventEmitter } from "../../../src/models/typed-event-emitter";
-import { ClientPrefix, HttpApiEvent, HttpApiEventHandlerMap, IdentityPrefix, IHttpOpts, Method } from "../../../src";
+import {
+    ClientPrefix,
+    HttpApiEvent,
+    HttpApiEventHandlerMap,
+    IdentityPrefix,
+    IHttpOpts,
+    MatrixError,
+    Method,
+} from "../../../src";
 import { emitPromise } from "../../test-utils/test-utils";
 import { defer, QueryDict } from "../../../src/utils";
-import { logger } from "../../../src/logger";
+import { Logger } from "../../../src/logger";

 describe("FetchHttpApi", () => {
    const baseUrl = "http://baseUrl";
@@ -231,13 +239,145 @@ describe("FetchHttpApi", () => {
    });

    describe("authedRequest", () => {
-        it("should not include token if unset", () => {
-            const fetchFn = jest.fn();
+        it("should not include token if unset", async () => {
+            const fetchFn = jest.fn().mockResolvedValue({ ok: true });
            const emitter = new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>();
            const api = new FetchHttpApi(emitter, { baseUrl, prefix, fetchFn });
-            api.authedRequest(Method.Post, "/account/password");
+            await api.authedRequest(Method.Post, "/account/password");
            expect(fetchFn.mock.calls[0][1].headers.Authorization).toBeUndefined();
        });
+
+        describe("with refresh token", () => {
+            const accessToken = "test-access-token";
+            const refreshToken = "test-refresh-token";
+
+            describe("when an unknown token error is encountered", () => {
+                const unknownTokenErrBody = {
+                    errcode: "M_UNKNOWN_TOKEN",
+                    error: "Token is not active",
+                    soft_logout: false,
+                };
+                const unknownTokenErr = new MatrixError(unknownTokenErrBody, 401);
+                const unknownTokenResponse = {
+                    ok: false,
+                    status: 401,
+                    headers: {
+                        get(name: string): string | null {
+                            return name === "Content-Type" ? "application/json" : null;
+                        },
+                    },
+                    text: jest.fn().mockResolvedValue(JSON.stringify(unknownTokenErrBody)),
+                };
+                const okayResponse = {
+                    ok: true,
+                    status: 200,
+                };
+
+                describe("without a tokenRefreshFunction", () => {
+                    it("should emit logout and throw", async () => {
+                        const fetchFn = jest.fn().mockResolvedValue(unknownTokenResponse);
+                        const emitter = new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>();
+                        jest.spyOn(emitter, "emit");
+                        const api = new FetchHttpApi(emitter, { baseUrl, prefix, fetchFn, accessToken, refreshToken });
+                        await expect(api.authedRequest(Method.Post, "/account/password")).rejects.toThrow(
+                            unknownTokenErr,
+                        );
+                        expect(emitter.emit).toHaveBeenCalledWith(HttpApiEvent.SessionLoggedOut, unknownTokenErr);
+                    });
+                });
+
+                describe("with a tokenRefreshFunction", () => {
+                    it("should emit logout and throw when token refresh fails", async () => {
+                        const error = new Error("uh oh");
+                        const tokenRefreshFunction = jest.fn().mockRejectedValue(error);
+                        const fetchFn = jest.fn().mockResolvedValue(unknownTokenResponse);
+                        const emitter = new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>();
+                        jest.spyOn(emitter, "emit");
+                        const api = new FetchHttpApi(emitter, {
+                            baseUrl,
+                            prefix,
+                            fetchFn,
+                            tokenRefreshFunction,
+                            accessToken,
+                            refreshToken,
+                        });
+                        await expect(api.authedRequest(Method.Post, "/account/password")).rejects.toThrow(
+                            unknownTokenErr,
+                        );
+                        expect(tokenRefreshFunction).toHaveBeenCalledWith(refreshToken);
+                        expect(emitter.emit).toHaveBeenCalledWith(HttpApiEvent.SessionLoggedOut, unknownTokenErr);
+                    });
+
+                    it("should refresh token and retry request", async () => {
+                        const newAccessToken = "new-access-token";
+                        const newRefreshToken = "new-refresh-token";
+                        const tokenRefreshFunction = jest.fn().mockResolvedValue({
+                            accessToken: newAccessToken,
+                            refreshToken: newRefreshToken,
+                        });
+                        const fetchFn = jest
+                            .fn()
+                            .mockResolvedValueOnce(unknownTokenResponse)
+                            .mockResolvedValueOnce(okayResponse);
+                        const emitter = new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>();
+                        jest.spyOn(emitter, "emit");
+                        const api = new FetchHttpApi(emitter, {
+                            baseUrl,
+                            prefix,
+                            fetchFn,
+                            tokenRefreshFunction,
+                            accessToken,
+                            refreshToken,
+                        });
+                        const result = await api.authedRequest(Method.Post, "/account/password");
+                        expect(result).toEqual(okayResponse);
+                        expect(tokenRefreshFunction).toHaveBeenCalledWith(refreshToken);
+
+                        expect(fetchFn).toHaveBeenCalledTimes(2);
+                        // uses new access token
+                        expect(fetchFn.mock.calls[1][1].headers.Authorization).toEqual("Bearer new-access-token");
+                        expect(emitter.emit).not.toHaveBeenCalledWith(HttpApiEvent.SessionLoggedOut, unknownTokenErr);
+                    });
+
+                    it("should only try to refresh the token once", async () => {
+                        const newAccessToken = "new-access-token";
+                        const newRefreshToken = "new-refresh-token";
+                        const tokenRefreshFunction = jest.fn().mockResolvedValue({
+                            accessToken: newAccessToken,
+                            refreshToken: newRefreshToken,
+                        });
+
+                        // fetch doesn't like our new or old tokens
+                        const fetchFn = jest.fn().mockResolvedValue(unknownTokenResponse);
+
+                        const emitter = new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>();
+                        jest.spyOn(emitter, "emit");
+                        const api = new FetchHttpApi(emitter, {
+                            baseUrl,
+                            prefix,
+                            fetchFn,
+                            tokenRefreshFunction,
+                            accessToken,
+                            refreshToken,
+                        });
+                        await expect(api.authedRequest(Method.Post, "/account/password")).rejects.toThrow(
+                            unknownTokenErr,
+                        );
+
+                        // tried to refresh the token once
+                        expect(tokenRefreshFunction).toHaveBeenCalledWith(refreshToken);
+                        expect(tokenRefreshFunction).toHaveBeenCalledTimes(1);
+
+                        expect(fetchFn).toHaveBeenCalledTimes(2);
+                        // uses new access token on retry
+                        expect(fetchFn.mock.calls[1][1].headers.Authorization).toEqual("Bearer new-access-token");
+
+                        // logged out after refreshed access token is rejected
+                        expect(emitter.emit).toHaveBeenCalledWith(HttpApiEvent.SessionLoggedOut, unknownTokenErr);
+                    });
+                });
+            });
+        });
    });

    describe("getUrl()", () => {
@@ -300,22 +440,29 @@ describe("FetchHttpApi", () => {
        jest.useFakeTimers();
        const deferred = defer<Response>();
        const fetchFn = jest.fn().mockReturnValue(deferred.promise);
-        jest.spyOn(logger, "debug").mockImplementation(() => {});
-        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), { baseUrl, prefix, fetchFn });
+        const mockLogger = {
+            debug: jest.fn(),
+        } as unknown as Mocked<Logger>;
+        const api = new FetchHttpApi(new TypedEventEmitter<any, any>(), {
+            baseUrl,
+            prefix,
+            fetchFn,
+            logger: mockLogger,
+        });
        const prom = api.requestOtherUrl(Method.Get, "https://server:8448/some/path?query=param#fragment");
        jest.advanceTimersByTime(1234);
        deferred.resolve({ ok: true, status: 200, text: () => Promise.resolve("RESPONSE") } as Response);
        await prom;
-        expect(logger.debug).not.toHaveBeenCalledWith("fragment");
-        expect(logger.debug).not.toHaveBeenCalledWith("query");
-        expect(logger.debug).not.toHaveBeenCalledWith("param");
-        expect(logger.debug).toHaveBeenCalledTimes(2);
-        expect(mocked(logger.debug).mock.calls[0]).toMatchInlineSnapshot(`
+        expect(mockLogger.debug).not.toHaveBeenCalledWith("fragment");
+        expect(mockLogger.debug).not.toHaveBeenCalledWith("query");
+        expect(mockLogger.debug).not.toHaveBeenCalledWith("param");
+        expect(mockLogger.debug).toHaveBeenCalledTimes(2);
+        expect(mockLogger.debug.mock.calls[0]).toMatchInlineSnapshot(`
            [
              "FetchHttpApi: --> GET https://server:8448/some/path?query=xxx",
            ]
        `);
-        expect(mocked(logger.debug).mock.calls[1]).toMatchInlineSnapshot(`
+        expect(mockLogger.debug.mock.calls[1]).toMatchInlineSnapshot(`
            [
              "FetchHttpApi: <-- GET https://server:8448/some/path?query=xxx [1234ms 200]",
            ]
@@ -328,6 +328,7 @@ describe("MatrixClient", function () {
                "storeFilter",
                "startup",
                "deleteAllData",
+                "setUserCreator",
            ] as const
        ).reduce((r, k) => {
            r[k] = jest.fn();
@@ -2210,8 +2211,7 @@ describe("MatrixClient", function () {
                    "org.matrix.msc3391": true,
                },
            };
-            jest.spyOn(client.http, "request").mockResolvedValue(versionsResponse);
-            const requestSpy = jest.spyOn(client.http, "authedRequest").mockImplementation(() => Promise.resolve());
+            const requestSpy = jest.spyOn(client.http, "authedRequest").mockResolvedValue(versionsResponse);
            const unstablePrefix = "/_matrix/client/unstable/org.matrix.msc3391";
            const path = `/user/${encodeURIComponent(userId)}/account_data/${eventType}`;

@@ -2249,8 +2249,7 @@ describe("MatrixClient", function () {
                    "org.matrix.msc3391": false,
                },
            };
-            jest.spyOn(client.http, "request").mockResolvedValue(versionsResponse);
-            const requestSpy = jest.spyOn(client.http, "authedRequest").mockImplementation(() => Promise.resolve());
+            const requestSpy = jest.spyOn(client.http, "authedRequest").mockResolvedValue(versionsResponse);
            const path = `/user/${encodeURIComponent(userId)}/account_data/${eventType}`;

            // populate version support
@@ -23,14 +23,13 @@ const membershipTemplate: CallMembershipData = {
    application: "m.call",
    device_id: "AAAAAAA",
    expires: 5000,
+    membershipID: "bloop",
 };

 function makeMockEvent(originTs = 0): MatrixEvent {
    return {
        getTs: jest.fn().mockReturnValue(originTs),
-        sender: {
-            userId: "@alice:example.org",
-        },
+        getSender: jest.fn().mockReturnValue("@alice:example.org"),
    } as unknown as MatrixEvent;
 }

@@ -86,7 +85,7 @@ describe("CallMembership", () => {

    it("considers memberships expired when local age large", () => {
        const fakeEvent = makeMockEvent(1000);
-        fakeEvent.getLocalAge = jest.fn().mockReturnValue(6000);
+        fakeEvent.localTimestamp = Date.now() - 6000;
        const membership = new CallMembership(fakeEvent, membershipTemplate);
        expect(membership.isExpired()).toEqual(true);
    });
@@ -14,11 +14,12 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

-import { EventTimeline, EventType, MatrixClient, Room } from "../../../src";
+import { EventTimeline, EventType, MatrixClient, MatrixError, MatrixEvent, Room } from "../../../src";
 import { CallMembershipData } from "../../../src/matrixrtc/CallMembership";
 import { MatrixRTCSession, MatrixRTCSessionEvent } from "../../../src/matrixrtc/MatrixRTCSession";
+import { EncryptionKeysEventContent } from "../../../src/matrixrtc/types";
 import { randomString } from "../../../src/randomstring";
-import { makeMockRoom, mockRTCEvent } from "./mocks";
+import { makeMockRoom, makeMockRoomState, mockRTCEvent } from "./mocks";

 const membershipTemplate: CallMembershipData = {
    call_id: "",
@@ -26,6 +27,7 @@ const membershipTemplate: CallMembershipData = {
    application: "m.call",
    device_id: "AAAAAAA",
    expires: 60 * 60 * 1000,
+    membershipID: "bloop",
 };

 const mockFocus = { type: "mock" };
@@ -56,14 +58,16 @@ describe("MatrixRTCSession", () => {
        expect(sess?.memberships[0].scope).toEqual("m.room");
        expect(sess?.memberships[0].application).toEqual("m.call");
        expect(sess?.memberships[0].deviceId).toEqual("AAAAAAA");
+        expect(sess?.memberships[0].membershipID).toEqual("bloop");
        expect(sess?.memberships[0].isExpired()).toEqual(false);
+        expect(sess?.callId).toEqual("");
    });

    it("ignores expired memberships events", () => {
        const expiredMembership = Object.assign({}, membershipTemplate);
        expiredMembership.expires = 1000;
        expiredMembership.device_id = "EXPIRED";
-        const mockRoom = makeMockRoom([membershipTemplate, expiredMembership], () => 10000);
+        const mockRoom = makeMockRoom([membershipTemplate, expiredMembership], 10000);

        sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
        expect(sess?.memberships.length).toEqual(1);
@@ -182,8 +186,15 @@ describe("MatrixRTCSession", () => {

    describe("joining", () => {
        let mockRoom: Room;
+        let sendStateEventMock: jest.Mock;
+        let sendEventMock: jest.Mock;

        beforeEach(() => {
+            sendStateEventMock = jest.fn();
+            sendEventMock = jest.fn();
+            client.sendStateEvent = sendStateEventMock;
+            client.sendEvent = sendEventMock;
+
            mockRoom = makeMockRoom([]);
            sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
        });
@@ -203,8 +214,6 @@ describe("MatrixRTCSession", () => {
        });

        it("sends a membership event when joining a call", () => {
-            client.sendStateEvent = jest.fn();
-
            sess!.joinRoomSession([mockFocus]);

            expect(client.sendStateEvent).toHaveBeenCalledWith(
@@ -219,6 +228,7 @@ describe("MatrixRTCSession", () => {
                            device_id: "AAAAAAA",
                            expires: 3600000,
                            foci_active: [{ type: "mock" }],
+                            membershipID: expect.stringMatching(".*"),
                        },
                    ],
                },
@@ -227,9 +237,6 @@ describe("MatrixRTCSession", () => {
        });

        it("does nothing if join called when already joined", () => {
-            const sendStateEventMock = jest.fn();
-            client.sendStateEvent = sendStateEventMock;
-
            sess!.joinRoomSession([mockFocus]);

            expect(client.sendStateEvent).toHaveBeenCalledTimes(1);
@@ -259,7 +266,7 @@ describe("MatrixRTCSession", () => {
                const timeElapsed = 60 * 60 * 1000 - 1000;
                mockRoom.getLiveTimeline().getState(EventTimeline.FORWARDS)!.getStateEvents = jest
                    .fn()
-                    .mockReturnValue(mockRTCEvent(eventContent.memberships, mockRoom.roomId, () => timeElapsed));
+                    .mockReturnValue(mockRTCEvent(eventContent.memberships, mockRoom.roomId, timeElapsed));

                const eventReSentPromise = new Promise<Record<string, any>>((r) => {
                    resolveFn = (_roomId: string, _type: string, val: Record<string, any>) => {
@@ -286,6 +293,7 @@ describe("MatrixRTCSession", () => {
                                expires: 3600000 * 2,
                                foci_active: [{ type: "mock" }],
                                created_ts: 1000,
+                                membershipID: expect.stringMatching(".*"),
                            },
                        ],
                    },
@@ -295,15 +303,244 @@ describe("MatrixRTCSession", () => {
                jest.useRealTimers();
            }
        });
+
+        it("creates a key when joining", () => {
+            sess!.joinRoomSession([mockFocus], true);
+            const keys = sess?.getKeysForParticipant("@alice:example.org", "AAAAAAA");
+            expect(keys).toHaveLength(1);
+
+            const allKeys = sess!.getEncryptionKeys();
+            expect(allKeys).toBeTruthy();
+            expect(Array.from(allKeys)).toHaveLength(1);
+        });
+
+        it("sends keys when joining", async () => {
+            const eventSentPromise = new Promise((resolve) => {
+                sendEventMock.mockImplementation(resolve);
+            });
+
+            sess!.joinRoomSession([mockFocus], true);
+
+            await eventSentPromise;
+
+            expect(sendEventMock).toHaveBeenCalledWith(expect.stringMatching(".*"), "io.element.call.encryption_keys", {
+                call_id: "",
+                device_id: "AAAAAAA",
+                keys: [
+                    {
+                        index: 0,
+                        key: expect.stringMatching(".*"),
+                    },
+                ],
+            });
+        });
+
+        it("retries key sends", async () => {
+            jest.useFakeTimers();
+            let firstEventSent = false;
+
+            try {
+                const eventSentPromise = new Promise<void>((resolve) => {
+                    sendEventMock.mockImplementation(() => {
+                        if (!firstEventSent) {
+                            jest.advanceTimersByTime(10000);
+
+                            firstEventSent = true;
+                            const e = new Error() as MatrixError;
+                            e.data = {};
+                            throw e;
+                        } else {
+                            resolve();
+                        }
+                    });
+                });
+
+                sess!.joinRoomSession([mockFocus], true);
+                jest.advanceTimersByTime(10000);
+
+                await eventSentPromise;
+
+                expect(sendEventMock).toHaveBeenCalledTimes(2);
+            } finally {
+                jest.useRealTimers();
+            }
+        });
+
+        it("cancels key send event that fail", async () => {
+            const eventSentinel = {} as unknown as MatrixEvent;
+
+            client.cancelPendingEvent = jest.fn();
+            sendEventMock.mockImplementation(() => {
+                const e = new Error() as MatrixError;
+                e.data = {};
+                e.event = eventSentinel;
+                throw e;
+            });
+
+            sess!.joinRoomSession([mockFocus], true);
+
+            expect(client.cancelPendingEvent).toHaveBeenCalledWith(eventSentinel);
+        });
+
+        it("Re-sends key if a new member joins", async () => {
+            jest.useFakeTimers();
+            try {
+                const mockRoom = makeMockRoom([membershipTemplate]);
+                sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
+
+                const keysSentPromise1 = new Promise((resolve) => {
+                    sendEventMock.mockImplementation(resolve);
+                });
+
+                sess.joinRoomSession([mockFocus], true);
+                await keysSentPromise1;
+
+                sendEventMock.mockClear();
+                jest.advanceTimersByTime(10000);
+
+                const keysSentPromise2 = new Promise((resolve) => {
+                    sendEventMock.mockImplementation(resolve);
+                });
+
+                const onMembershipsChanged = jest.fn();
+                sess.on(MatrixRTCSessionEvent.MembershipsChanged, onMembershipsChanged);
+
+                const member2 = Object.assign({}, membershipTemplate, {
+                    device_id: "BBBBBBB",
+                });
+
+                mockRoom.getLiveTimeline().getState = jest
+                    .fn()
+                    .mockReturnValue(makeMockRoomState([membershipTemplate, member2], mockRoom.roomId, undefined));
+                sess.onMembershipUpdate();
+
+                await keysSentPromise2;
+
+                expect(sendEventMock).toHaveBeenCalled();
+            } finally {
+                jest.useRealTimers();
+            }
+        });
+
+        it("Rotates key if a member leaves", async () => {
+            jest.useFakeTimers();
+            try {
+                const member2 = Object.assign({}, membershipTemplate, {
+                    device_id: "BBBBBBB",
+                });
+                const mockRoom = makeMockRoom([membershipTemplate, member2]);
+                sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
+
+                const onMyEncryptionKeyChanged = jest.fn();
+                sess.on(
+                    MatrixRTCSessionEvent.EncryptionKeyChanged,
+                    (_key: Uint8Array, _idx: number, participantId: string) => {
+                        if (participantId === `${client.getUserId()}:${client.getDeviceId()}`) {
+                            onMyEncryptionKeyChanged();
+                        }
+                    },
+                );
+
+                const keysSentPromise1 = new Promise<EncryptionKeysEventContent>((resolve) => {
+                    sendEventMock.mockImplementation((_roomId, _evType, payload) => resolve(payload));
+                });
+
+                sess.joinRoomSession([mockFocus], true);
+                const firstKeysPayload = await keysSentPromise1;
+                expect(firstKeysPayload.keys).toHaveLength(1);
+
+                sendEventMock.mockClear();
+
+                const keysSentPromise2 = new Promise<EncryptionKeysEventContent>((resolve) => {
+                    sendEventMock.mockImplementation((_roomId, _evType, payload) => resolve(payload));
+                });
+
+                mockRoom.getLiveTimeline().getState = jest
+                    .fn()
+                    .mockReturnValue(makeMockRoomState([membershipTemplate], mockRoom.roomId, undefined));
+                sess.onMembershipUpdate();
+
+                jest.advanceTimersByTime(10000);
+
+                const secondKeysPayload = await keysSentPromise2;
+
+                expect(secondKeysPayload.keys).toHaveLength(2);
+                expect(onMyEncryptionKeyChanged).toHaveBeenCalledTimes(2);
+            } finally {
+                jest.useRealTimers();
+            }
+        });
+
+        it("Doesn't re-send key immediately", async () => {
+            const realSetImmediate = setImmediate;
+            jest.useFakeTimers();
+            try {
+                const mockRoom = makeMockRoom([membershipTemplate]);
+                sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
+
+                const keysSentPromise1 = new Promise((resolve) => {
+                    sendEventMock.mockImplementation(resolve);
+                });
+
+                sess.joinRoomSession([mockFocus], true);
+                await keysSentPromise1;
+
+                sendEventMock.mockClear();
+
+                const onMembershipsChanged = jest.fn();
+                sess.on(MatrixRTCSessionEvent.MembershipsChanged, onMembershipsChanged);
+
+                const member2 = Object.assign({}, membershipTemplate, {
+                    device_id: "BBBBBBB",
+                });
+
+                mockRoom.getLiveTimeline().getState = jest
+                    .fn()
+                    .mockReturnValue(makeMockRoomState([membershipTemplate, member2], mockRoom.roomId, undefined));
+                sess.onMembershipUpdate();
+
+                await new Promise((resolve) => {
+                    realSetImmediate(resolve);
+                });
+
+                expect(sendEventMock).not.toHaveBeenCalled();
+            } finally {
+                jest.useRealTimers();
+            }
+        });
+    });
+
+    it("Does not emits if no membership changes", () => {
+        const mockRoom = makeMockRoom([membershipTemplate]);
+        sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
+
+        const onMembershipsChanged = jest.fn();
+        sess.on(MatrixRTCSessionEvent.MembershipsChanged, onMembershipsChanged);
+        sess.onMembershipUpdate();
+
+        expect(onMembershipsChanged).not.toHaveBeenCalled();
+    });
+
+    it("Emits on membership changes", () => {
+        const mockRoom = makeMockRoom([membershipTemplate]);
+        sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
+
+        const onMembershipsChanged = jest.fn();
+        sess.on(MatrixRTCSessionEvent.MembershipsChanged, onMembershipsChanged);
+
+        mockRoom.getLiveTimeline().getState = jest
+            .fn()
+            .mockReturnValue(makeMockRoomState([], mockRoom.roomId, undefined));
+        sess.onMembershipUpdate();
+
+        expect(onMembershipsChanged).toHaveBeenCalled();
    });

    it("emits an event at the time a membership event expires", () => {
        jest.useFakeTimers();
        try {
-            let eventAge = 0;
-
            const membership = Object.assign({}, membershipTemplate);
-            const mockRoom = makeMockRoom([membership], () => eventAge);
+            const mockRoom = makeMockRoom([membership], 0);

            sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
            const membershipObject = sess.memberships[0];
@@ -311,7 +548,6 @@ describe("MatrixRTCSession", () => {
            const onMembershipsChanged = jest.fn();
            sess.on(MatrixRTCSessionEvent.MembershipsChanged, onMembershipsChanged);

-            eventAge = 61 * 1000 * 1000;
            jest.advanceTimersByTime(61 * 1000 * 1000);

            expect(onMembershipsChanged).toHaveBeenCalledWith([membershipObject], []);
@@ -322,46 +558,49 @@ describe("MatrixRTCSession", () => {
    });

    it("prunes expired memberships on update", () => {
-        client.sendStateEvent = jest.fn();
+        jest.useFakeTimers();
+        try {
+            client.sendStateEvent = jest.fn();

-        let eventAge = 0;
-
-        const mockRoom = makeMockRoom(
-            [
+            const mockMemberships = [
                Object.assign({}, membershipTemplate, {
                    device_id: "OTHERDEVICE",
                    expires: 1000,
                }),
-            ],
-            () => eventAge,
-        );
-        sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
+            ];
+            const mockRoomNoExpired = makeMockRoom(mockMemberships, 0);

-        // sanity check
-        expect(sess.memberships).toHaveLength(1);
-        expect(sess.memberships[0].deviceId).toEqual("OTHERDEVICE");
+            sess = MatrixRTCSession.roomSessionForRoom(client, mockRoomNoExpired);

-        eventAge = 10000;
+            // sanity check
+            expect(sess.memberships).toHaveLength(1);
+            expect(sess.memberships[0].deviceId).toEqual("OTHERDEVICE");

-        sess.joinRoomSession([mockFocus]);
+            jest.advanceTimersByTime(10000);

-        expect(client.sendStateEvent).toHaveBeenCalledWith(
-            mockRoom!.roomId,
-            EventType.GroupCallMemberPrefix,
-            {
-                memberships: [
-                    {
-                        application: "m.call",
-                        scope: "m.room",
-                        call_id: "",
-                        device_id: "AAAAAAA",
-                        expires: 3600000,
-                        foci_active: [mockFocus],
-                    },
-                ],
-            },
-            "@alice:example.org",
-        );
+            sess.joinRoomSession([mockFocus]);
+
+            expect(client.sendStateEvent).toHaveBeenCalledWith(
+                mockRoomNoExpired!.roomId,
+                EventType.GroupCallMemberPrefix,
+                {
+                    memberships: [
+                        {
+                            application: "m.call",
+                            scope: "m.room",
+                            call_id: "",
+                            device_id: "AAAAAAA",
+                            expires: 3600000,
+                            foci_active: [mockFocus],
+                            membershipID: expect.stringMatching(".*"),
+                        },
+                    ],
+                },
+                "@alice:example.org",
+            );
+        } finally {
+            jest.useRealTimers();
+        }
    });

    it("fills in created_ts for other memberships on update", () => {
@@ -388,6 +627,7 @@ describe("MatrixRTCSession", () => {
                        device_id: "OTHERDEVICE",
                        expires: 3600000,
                        created_ts: 1000,
+                        membershipID: expect.stringMatching(".*"),
                    },
                    {
                        application: "m.call",
@@ -396,10 +636,83 @@ describe("MatrixRTCSession", () => {
                        device_id: "AAAAAAA",
                        expires: 3600000,
                        foci_active: [mockFocus],
+                        membershipID: expect.stringMatching(".*"),
                    },
                ],
            },
            "@alice:example.org",
        );
    });
+
+    it("collects keys from encryption events", () => {
+        const mockRoom = makeMockRoom([membershipTemplate]);
+        sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
+        sess.onCallEncryption({
+            getType: jest.fn().mockReturnValue("io.element.call.encryption_keys"),
+            getContent: jest.fn().mockReturnValue({
+                device_id: "bobsphone",
+                call_id: "",
+                keys: [
+                    {
+                        index: 0,
+                        key: "dGhpcyBpcyB0aGUga2V5",
+                    },
+                ],
+            }),
+            getSender: jest.fn().mockReturnValue("@bob:example.org"),
+        } as unknown as MatrixEvent);
+
+        const bobKeys = sess.getKeysForParticipant("@bob:example.org", "bobsphone")!;
+        expect(bobKeys).toHaveLength(1);
+        expect(bobKeys[0]).toEqual(Buffer.from("this is the key", "utf-8"));
+    });
+
+    it("collects keys at non-zero indices", () => {
+        const mockRoom = makeMockRoom([membershipTemplate]);
+        sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
+        sess.onCallEncryption({
+            getType: jest.fn().mockReturnValue("io.element.call.encryption_keys"),
+            getContent: jest.fn().mockReturnValue({
+                device_id: "bobsphone",
+                call_id: "",
+                keys: [
+                    {
+                        index: 4,
+                        key: "dGhpcyBpcyB0aGUga2V5",
+                    },
+                ],
+            }),
+            getSender: jest.fn().mockReturnValue("@bob:example.org"),
+        } as unknown as MatrixEvent);
+
+        const bobKeys = sess.getKeysForParticipant("@bob:example.org", "bobsphone")!;
+        expect(bobKeys).toHaveLength(5);
+        expect(bobKeys[0]).toBeFalsy();
+        expect(bobKeys[1]).toBeFalsy();
+        expect(bobKeys[2]).toBeFalsy();
+        expect(bobKeys[3]).toBeFalsy();
+        expect(bobKeys[4]).toEqual(Buffer.from("this is the key", "utf-8"));
+    });
+
+    it("ignores keys event for the local participant", () => {
+        const mockRoom = makeMockRoom([membershipTemplate]);
+        sess = MatrixRTCSession.roomSessionForRoom(client, mockRoom);
+        sess.onCallEncryption({
+            getType: jest.fn().mockReturnValue("io.element.call.encryption_keys"),
+            getContent: jest.fn().mockReturnValue({
+                device_id: client.getDeviceId(),
+                call_id: "",
+                keys: [
+                    {
+                        index: 4,
+                        key: "dGhpcyBpcyB0aGUga2V5",
+                    },
+                ],
+            }),
+            getSender: jest.fn().mockReturnValue(client.getUserId()),
+        } as unknown as MatrixEvent);
+
+        const myKeys = sess.getKeysForParticipant(client.getUserId()!, client.getDeviceId()!)!;
+        expect(myKeys).toBeFalsy();
+    });
 });
@@ -14,7 +14,15 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

-import { ClientEvent, EventTimeline, MatrixClient } from "../../../src";
+import {
+    ClientEvent,
+    EventTimeline,
+    EventType,
+    IRoomTimelineData,
+    MatrixClient,
+    MatrixEvent,
+    RoomEvent,
+} from "../../../src";
 import { RoomStateEvent } from "../../../src/models/room-state";
 import { CallMembershipData } from "../../../src/matrixrtc/CallMembership";
 import { MatrixRTCSessionManagerEvents } from "../../../src/matrixrtc/MatrixRTCSessionManager";
@@ -26,6 +34,7 @@ const membershipTemplate: CallMembershipData = {
    application: "m.call",
    device_id: "AAAAAAA",
    expires: 60 * 60 * 1000,
+    membershipID: "bloop",
 };

 describe("MatrixRTCSessionManager", () => {
@@ -77,4 +86,26 @@ describe("MatrixRTCSessionManager", () => {

        expect(onEnded).toHaveBeenCalledWith(room1.roomId, client.matrixRTC.getActiveRoomSession(room1));
    });
+
+    it("Calls onCallEncryption on encryption keys event", () => {
+        const room1 = makeMockRoom([membershipTemplate]);
+        jest.spyOn(client, "getRooms").mockReturnValue([room1]);
+        jest.spyOn(client, "getRoom").mockReturnValue(room1);
+
+        client.emit(ClientEvent.Room, room1);
+        const onCallEncryptionMock = jest.fn();
+        client.matrixRTC.getRoomSession(room1).onCallEncryption = onCallEncryptionMock;
+
+        const timelineEvent = {
+            getType: jest.fn().mockReturnValue(EventType.CallEncryptionKeysPrefix),
+            getContent: jest.fn().mockReturnValue({}),
+            getSender: jest.fn().mockReturnValue("@mock:user.example"),
+            getRoomId: jest.fn().mockReturnValue("!room:id"),
+            sender: {
+                userId: "@mock:user.example",
+            },
+        } as unknown as MatrixEvent;
+        client.emit(RoomEvent.Timeline, timelineEvent, undefined, undefined, false, {} as IRoomTimelineData);
+        expect(onCallEncryptionMock).toHaveBeenCalled();
+    });
 });
@@ -18,37 +18,29 @@ import { EventType, MatrixEvent, Room } from "../../../src";
 import { CallMembershipData } from "../../../src/matrixrtc/CallMembership";
 import { randomString } from "../../../src/randomstring";

-export function makeMockRoom(
-    memberships: CallMembershipData[],
-    getLocalAge: (() => number) | undefined = undefined,
-): Room {
+export function makeMockRoom(memberships: CallMembershipData[], localAge: number | null = null): Room {
    const roomId = randomString(8);
+    // Caching roomState here so it does not get recreated when calling `getLiveTimeline.getState()`
+    const roomState = makeMockRoomState(memberships, roomId, localAge);
    return {
        roomId: roomId,
        getLiveTimeline: jest.fn().mockReturnValue({
-            getState: jest.fn().mockReturnValue(makeMockRoomState(memberships, roomId, getLocalAge)),
+            getState: jest.fn().mockReturnValue(roomState),
        }),
    } as unknown as Room;
 }

-function makeMockRoomState(memberships: CallMembershipData[], roomId: string, getLocalAge: (() => number) | undefined) {
+export function makeMockRoomState(memberships: CallMembershipData[], roomId: string, localAge: number | null = null) {
+    const event = mockRTCEvent(memberships, roomId, localAge);
    return {
        getStateEvents: (_: string, stateKey: string) => {
-            const event = mockRTCEvent(memberships, roomId, getLocalAge);
-
            if (stateKey !== undefined) return event;
            return [event];
        },
    };
 }

-export function mockRTCEvent(
-    memberships: CallMembershipData[],
-    roomId: string,
-    getLocalAge: (() => number) | undefined,
-): MatrixEvent {
-    const getLocalAgeFn = getLocalAge ?? (() => 10);
-
+export function mockRTCEvent(memberships: CallMembershipData[], roomId: string, localAge: number | null): MatrixEvent {
    return {
        getType: jest.fn().mockReturnValue(EventType.GroupCallMemberPrefix),
        getContent: jest.fn().mockReturnValue({
@@ -56,8 +48,7 @@ export function mockRTCEvent(
        }),
        getSender: jest.fn().mockReturnValue("@mock:user.example"),
        getTs: jest.fn().mockReturnValue(1000),
-        getLocalAge: getLocalAgeFn,
-        localTimestamp: Date.now(),
+        localTimestamp: Date.now() - (localAge ?? 10),
        getRoomId: jest.fn().mockReturnValue(roomId),
        sender: {
            userId: "@mock:user.example",
@@ -213,7 +213,7 @@ describe("MSC3089Branch", () => {
                    expect(eventId).toEqual(fileEventId);
                    return fileEvent;
                },
-            } as EventTimelineSet);
+            }) as EventTimelineSet;
        client.mxcUrlToHttp = (mxc: string) => {
            expect(mxc).toEqual("mxc://" + mxcLatter);
            return `https://example.org/_matrix/media/v1/download/${mxcLatter}`;
@@ -239,7 +239,7 @@ describe("MSC3089Branch", () => {
                    expect(eventId).toEqual(fileEventId);
                    return fileEvent;
                },
-            } as EventTimelineSet);
+            }) as EventTimelineSet;
        client.mxcUrlToHttp = (mxc: string) => {
            expect(mxc).toEqual("mxc://" + mxcLatter);
            return `https://example.org/_matrix/media/v1/download/${mxcLatter}`;
@@ -332,7 +332,7 @@ describe("MSC3089Branch", () => {
                getId: () => "$unknown",
            },
        ];
-        staticRoom.getLiveTimeline = () => ({ getEvents: () => events } as EventTimeline);
+        staticRoom.getLiveTimeline = () => ({ getEvents: () => events }) as EventTimeline;

        directory.getFile = (evId: string) => {
            expect(evId).toEqual(fileEventId);
@@ -399,7 +399,7 @@ describe("MSC3089TreeSpace", () => {
                ];
            },
        };
-        client.getRoom = () => ({} as Room); // to appease the TreeSpace constructor
+        client.getRoom = () => ({}) as Room; // to appease the TreeSpace constructor

        const getFn = jest.fn().mockImplementation((roomId: string) => {
            if (roomId === thirdChildRoom) {
@@ -422,7 +422,7 @@ describe("MSC3089TreeSpace", () => {
    });

    it("should find specific directories", () => {
-        client.getRoom = () => ({} as Room); // to appease the TreeSpace constructor
+        client.getRoom = () => ({}) as Room; // to appease the TreeSpace constructor

        // Only mocking used API
        const firstSubdirectory = { roomId: "!first:example.org" } as any as MSC3089TreeSpace;
@@ -14,10 +14,19 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

+import { MockedObject } from "jest-mock";
+
 import { MatrixEvent, MatrixEventEvent } from "../../../src/models/event";
 import { emitPromise } from "../../test-utils/test-utils";
 import { Crypto, IEventDecryptionResult } from "../../../src/crypto";
-import { IAnnotatedPushRule, PushRuleActionName, TweakName } from "../../../src";
+import {
+    IAnnotatedPushRule,
+    MatrixClient,
+    PushRuleActionName,
+    Room,
+    THREAD_RELATION_TYPE,
+    TweakName,
+} from "../../../src";

 describe("MatrixEvent", () => {
    it("should create copies of itself", () => {
@@ -61,31 +70,264 @@ describe("MatrixEvent", () => {
        expect(a.toSnapshot().isEquivalentTo(b)).toBe(false);
    });

-    it("should prune clearEvent when being redacted", () => {
-        const ev = new MatrixEvent({
-            type: "m.room.message",
-            content: {
-                body: "Test",
-            },
-            event_id: "$event1:server",
+    describe("redaction", () => {
+        it("should prune clearEvent when being redacted", () => {
+            const ev = createEvent("$event1:server", "Test");
+
+            expect(ev.getContent().body).toBe("Test");
+            expect(ev.getWireContent().body).toBe("Test");
+            ev.makeEncrypted("m.room.encrypted", { ciphertext: "xyz" }, "", "");
+            expect(ev.getContent().body).toBe("Test");
+            expect(ev.getWireContent().body).toBeUndefined();
+            expect(ev.getWireContent().ciphertext).toBe("xyz");
+
+            const mockClient = {} as unknown as MockedObject<MatrixClient>;
+            const room = new Room("!roomid:e.xyz", mockClient, "myname");
+            const redaction = createRedaction(ev.getId()!);
+
+            ev.makeRedacted(redaction, room);
+            expect(ev.getContent().body).toBeUndefined();
+            expect(ev.getWireContent().body).toBeUndefined();
+            expect(ev.getWireContent().ciphertext).toBeUndefined();
        });

-        expect(ev.getContent().body).toBe("Test");
-        expect(ev.getWireContent().body).toBe("Test");
-        ev.makeEncrypted("m.room.encrypted", { ciphertext: "xyz" }, "", "");
-        expect(ev.getContent().body).toBe("Test");
-        expect(ev.getWireContent().body).toBeUndefined();
-        expect(ev.getWireContent().ciphertext).toBe("xyz");
+        it("should remain in the main timeline when redacted", async () => {
+            // Given an event in the main timeline
+            const mockClient = createMockClient();
+            const room = new Room("!roomid:e.xyz", mockClient, "myname");
+            const ev = createEvent("$event1:server");

-        const redaction = new MatrixEvent({
-            type: "m.room.redaction",
-            redacts: ev.getId(),
+            await room.addLiveEvents([ev]);
+            await room.createThreadsTimelineSets();
+            expect(ev.threadRootId).toBeUndefined();
+            expect(mainTimelineLiveEventIds(room)).toEqual([ev.getId()]);
+
+            // When I redact it
+            const redaction = createRedaction(ev.getId()!);
+            ev.makeRedacted(redaction, room);
+
+            // Then it remains in the main timeline
+            expect(ev.threadRootId).toBeUndefined();
+            expect(mainTimelineLiveEventIds(room)).toEqual([ev.getId()]);
        });

-        ev.makeRedacted(redaction);
-        expect(ev.getContent().body).toBeUndefined();
-        expect(ev.getWireContent().body).toBeUndefined();
-        expect(ev.getWireContent().ciphertext).toBeUndefined();
+        it("should keep thread roots in both timelines when redacted", async () => {
+            // Given a thread exists
+            const mockClient = createMockClient();
+            const room = new Room("!roomid:e.xyz", mockClient, "myname");
+            const threadRoot = createEvent("$threadroot:server");
+            const ev = createThreadedEvent("$event1:server", threadRoot.getId()!);
+
+            await room.addLiveEvents([threadRoot, ev]);
+            await room.createThreadsTimelineSets();
+            expect(threadRoot.threadRootId).toEqual(threadRoot.getId());
+            expect(mainTimelineLiveEventIds(room)).toEqual([threadRoot.getId()]);
+            expect(threadLiveEventIds(room, 0)).toEqual([threadRoot.getId(), ev.getId()]);
+
+            // When I redact the thread root
+            const redaction = createRedaction(ev.getId()!);
+            threadRoot.makeRedacted(redaction, room);
+
+            // Then it remains in the main timeline and the thread
+            expect(threadRoot.threadRootId).toEqual(threadRoot.getId());
+            expect(mainTimelineLiveEventIds(room)).toEqual([threadRoot.getId()]);
+            expect(threadLiveEventIds(room, 0)).toEqual([threadRoot.getId(), ev.getId()]);
+        });
+
+        it("should move into the main timeline when redacted", async () => {
+            // Given an event in a thread
+            const mockClient = createMockClient();
+            const room = new Room("!roomid:e.xyz", mockClient, "myname");
+            const threadRoot = createEvent("$threadroot:server");
+            const ev = createThreadedEvent("$event1:server", threadRoot.getId()!);
+
+            await room.addLiveEvents([threadRoot, ev]);
+            await room.createThreadsTimelineSets();
+            expect(ev.threadRootId).toEqual(threadRoot.getId());
+            expect(mainTimelineLiveEventIds(room)).toEqual([threadRoot.getId()]);
+            expect(threadLiveEventIds(room, 0)).toEqual([threadRoot.getId(), ev.getId()]);
+
+            // When I redact it
+            const redaction = createRedaction(ev.getId()!);
+            ev.makeRedacted(redaction, room);
+
+            // Then it disappears from the thread and appears in the main timeline
+            expect(ev.threadRootId).toBeUndefined();
+            expect(mainTimelineLiveEventIds(room)).toEqual([threadRoot.getId(), ev.getId()]);
+            expect(threadLiveEventIds(room, 0)).not.toContain(ev.getId());
+        });
+
+        it("should move reactions to a redacted event into the main timeline", async () => {
+            // Given an event in a thread with a reaction
+            const mockClient = createMockClient();
+            const room = new Room("!roomid:e.xyz", mockClient, "myname");
+            const threadRoot = createEvent("$threadroot:server");
+            const ev = createThreadedEvent("$event1:server", threadRoot.getId()!);
+            const reaction = createReactionEvent("$reaction:server", ev.getId()!);
+
+            await room.addLiveEvents([threadRoot, ev, reaction]);
+            await room.createThreadsTimelineSets();
+            expect(reaction.threadRootId).toEqual(threadRoot.getId());
+            expect(mainTimelineLiveEventIds(room)).toEqual([threadRoot.getId()]);
+            expect(threadLiveEventIds(room, 0)).toEqual([threadRoot.getId(), ev.getId(), reaction.getId()]);
+
+            // When I redact the event
+            const redaction = createRedaction(ev.getId()!);
+            ev.makeRedacted(redaction, room);
+
+            // Then the reaction moves into the main timeline
+            expect(reaction.threadRootId).toBeUndefined();
+            expect(mainTimelineLiveEventIds(room)).toEqual([threadRoot.getId(), ev.getId(), reaction.getId()]);
+            expect(threadLiveEventIds(room, 0)).not.toContain(reaction.getId());
+        });
+
+        it("should move edits of a redacted event into the main timeline", async () => {
+            // Given an event in a thread with a reaction
+            const mockClient = createMockClient();
+            const room = new Room("!roomid:e.xyz", mockClient, "myname");
+            const threadRoot = createEvent("$threadroot:server");
+            const ev = createThreadedEvent("$event1:server", threadRoot.getId()!);
+            const edit = createEditEvent("$edit:server", ev.getId()!);
+
+            await room.addLiveEvents([threadRoot, ev, edit]);
+            await room.createThreadsTimelineSets();
+            expect(edit.threadRootId).toEqual(threadRoot.getId());
+            expect(mainTimelineLiveEventIds(room)).toEqual([threadRoot.getId()]);
+            expect(threadLiveEventIds(room, 0)).toEqual([threadRoot.getId(), ev.getId(), edit.getId()]);
+
+            // When I redact the event
+            const redaction = createRedaction(ev.getId()!);
+            ev.makeRedacted(redaction, room);
+
+            // Then the edit moves into the main timeline
+            expect(edit.threadRootId).toBeUndefined();
+            expect(mainTimelineLiveEventIds(room)).toEqual([threadRoot.getId(), ev.getId(), edit.getId()]);
+            expect(threadLiveEventIds(room, 0)).not.toContain(edit.getId());
+        });
+
+        it("should move reactions to replies to replies a redacted event into the main timeline", async () => {
+            // Given an event in a thread with a reaction
+            const mockClient = createMockClient();
+            const room = new Room("!roomid:e.xyz", mockClient, "myname");
+            const threadRoot = createEvent("$threadroot:server");
+            const ev = createThreadedEvent("$event1:server", threadRoot.getId()!);
+            const reply1 = createReplyEvent("$reply1:server", ev.getId()!);
+            const reply2 = createReplyEvent("$reply2:server", reply1.getId()!);
+            const reaction = createReactionEvent("$reaction:server", reply2.getId()!);
+
+            await room.addLiveEvents([threadRoot, ev, reply1, reply2, reaction]);
+            await room.createThreadsTimelineSets();
+            expect(reaction.threadRootId).toEqual(threadRoot.getId());
+            expect(mainTimelineLiveEventIds(room)).toEqual([threadRoot.getId()]);
+            expect(threadLiveEventIds(room, 0)).toEqual([
+                threadRoot.getId(),
+                ev.getId(),
+                reply1.getId(),
+                reply2.getId(),
+                reaction.getId(),
+            ]);
+
+            // When I redact the event
+            const redaction = createRedaction(ev.getId()!);
+            ev.makeRedacted(redaction, room);
+
+            // Then the replies move to the main thread and the reaction disappears
+            expect(reaction.threadRootId).toBeUndefined();
+            expect(mainTimelineLiveEventIds(room)).toEqual([
+                threadRoot.getId(),
+                ev.getId(),
+                reply1.getId(),
+                reply2.getId(),
+                reaction.getId(),
+            ]);
+            expect(threadLiveEventIds(room, 0)).not.toContain(reply1.getId());
+            expect(threadLiveEventIds(room, 0)).not.toContain(reply2.getId());
+            expect(threadLiveEventIds(room, 0)).not.toContain(reaction.getId());
+        });
+
+        function createMockClient(): MatrixClient {
+            return {
+                supportsThreads: jest.fn().mockReturnValue(true),
+                decryptEventIfNeeded: jest.fn().mockReturnThis(),
+                getUserId: jest.fn().mockReturnValue("@user:server"),
+            } as unknown as MockedObject<MatrixClient>;
+        }
+
+        function createEvent(eventId: string, body?: string): MatrixEvent {
+            return new MatrixEvent({
+                type: "m.room.message",
+                content: {
+                    body: body ?? eventId,
+                },
+                event_id: eventId,
+            });
+        }
+
+        function createThreadedEvent(eventId: string, threadRootId: string): MatrixEvent {
+            return new MatrixEvent({
+                type: "m.room.message",
+                content: {
+                    "body": eventId,
+                    "m.relates_to": {
+                        rel_type: THREAD_RELATION_TYPE.name,
+                        event_id: threadRootId,
+                    },
+                },
+                event_id: eventId,
+            });
+        }
+
+        function createEditEvent(eventId: string, repliedToId: string): MatrixEvent {
+            return new MatrixEvent({
+                type: "m.room.message",
+                content: {
+                    "body": "Edited",
+                    "m.new_content": {
+                        body: "Edited",
+                    },
+                    "m.relates_to": {
+                        event_id: repliedToId,
+                        rel_type: "m.replace",
+                    },
+                },
+                event_id: eventId,
+            });
+        }
+
+        function createReplyEvent(eventId: string, repliedToId: string): MatrixEvent {
+            return new MatrixEvent({
+                type: "m.room.message",
+                content: {
+                    "m.relates_to": {
+                        event_id: repliedToId,
+                        key: "x",
+                        rel_type: "m.in_reply_to",
+                    },
+                },
+                event_id: eventId,
+            });
+        }
+
+        function createReactionEvent(eventId: string, reactedToId: string): MatrixEvent {
+            return new MatrixEvent({
+                type: "m.reaction",
+                content: {
+                    "m.relates_to": {
+                        event_id: reactedToId,
+                        key: "x",
+                        rel_type: "m.annotation",
+                    },
+                },
+                event_id: eventId,
+            });
+        }
+
+        function createRedaction(redactedEventid: string): MatrixEvent {
+            return new MatrixEvent({
+                type: "m.room.redaction",
+                redacts: redactedEventid,
+            });
+        }
    });

    describe("applyVisibilityEvent", () => {
@@ -330,3 +572,19 @@ describe("MatrixEvent", () => {
        expect(stateEvent.threadRootId).toBeUndefined();
    });
 });
+
+function mainTimelineLiveEventIds(room: Room): Array<string> {
+    return room
+        .getLiveTimeline()
+        .getEvents()
+        .map((e) => e.getId()!);
+}
+
+function threadLiveEventIds(room: Room, threadIndex: number): Array<string> {
+    return room
+        .getThreads()
+        [threadIndex].getUnfilteredTimelineSet()
+        .getLiveTimeline()
+        .getEvents()
+        .map((e) => e.getId()!);
+}
@@ -0,0 +1,541 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { FeatureSupport, MatrixClient, MatrixEvent, ReceiptContent, THREAD_RELATION_TYPE, Thread } from "../../../src";
+import { Room } from "../../../src/models/room";
+
+/**
+ * Note, these tests check the functionality of the RoomReceipts class, but most
+ * of them access that functionality via the surrounding Room class, because a
+ * room is required for RoomReceipts to function, and this matches the pattern
+ * of how this code is used in the wild.
+ */
+describe("RoomReceipts", () => {
+    beforeAll(() => {
+        jest.replaceProperty(Thread, "hasServerSideSupport", FeatureSupport.Stable);
+    });
+
+    afterAll(() => {
+        jest.restoreAllMocks();
+    });
+
+    it("reports events unread if there are no receipts", () => {
+        // Given there are no receipts in the room
+        const room = createRoom();
+        const [event] = createEvent();
+        room.addLiveEvents([event]);
+
+        // When I ask about any event, then it is unread
+        expect(room.hasUserReadEvent(readerId, event.getId()!)).toBe(false);
+    });
+
+    it("reports events we sent as read even if there are no (real) receipts", () => {
+        // Given there are no receipts in the room
+        const room = createRoom();
+        const [event] = createEventSentBy(readerId);
+        room.addLiveEvents([event]);
+
+        // When I ask about an event I sent, it is read (because a synthetic
+        // receipt was created and stored in RoomReceipts)
+        expect(room.hasUserReadEvent(readerId, event.getId()!)).toBe(true);
+    });
+
+    it("reports read if we receive an unthreaded receipt for this event", () => {
+        // Given my event exists and is unread
+        const room = createRoom();
+        const [event, eventId] = createEvent();
+        room.addLiveEvents([event]);
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+        // When we receive a receipt for this event+user
+        room.addReceipt(createReceipt(readerId, event));
+
+        // Then that event is read
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(true);
+    });
+
+    it("reports read if we receive an unthreaded receipt for a later event", () => {
+        // Given we have 2 events
+        const room = createRoom();
+        const [event1, event1Id] = createEvent();
+        const [event2] = createEvent();
+        room.addLiveEvents([event1, event2]);
+
+        // When we receive a receipt for the later event
+        room.addReceipt(createReceipt(readerId, event2));
+
+        // Then the earlier one is read
+        expect(room.hasUserReadEvent(readerId, event1Id)).toBe(true);
+    });
+
+    it("reports read for a non-live event if we receive an unthreaded receipt for a live one", () => {
+        // Given we have 2 events: one live and one old
+        const room = createRoom();
+        const [oldEvent, oldEventId] = createEvent();
+        const [liveEvent] = createEvent();
+        room.addLiveEvents([liveEvent]);
+        createOldTimeline(room, [oldEvent]);
+
+        // When we receive a receipt for the live event
+        room.addReceipt(createReceipt(readerId, liveEvent));
+
+        // Then the earlier one is read
+        expect(room.hasUserReadEvent(readerId, oldEventId)).toBe(true);
+    });
+
+    it("compares by timestamp if two events are in separate old timelines", () => {
+        // Given we have 2 events, both in old timelines, with event2 after
+        // event1 in terms of timestamps
+        const room = createRoom();
+        const [event1, event1Id] = createEvent();
+        const [event2, event2Id] = createEvent();
+        event1.event.origin_server_ts = 1;
+        event2.event.origin_server_ts = 2;
+        createOldTimeline(room, [event1]);
+        createOldTimeline(room, [event2]);
+
+        // When we receive a receipt for the older event
+        room.addReceipt(createReceipt(readerId, event1));
+
+        // Then the earlier one is read and the later one is not
+        expect(room.hasUserReadEvent(readerId, event1Id)).toBe(true);
+        expect(room.hasUserReadEvent(readerId, event2Id)).toBe(false);
+    });
+
+    it("reports unread if we receive an unthreaded receipt for an earlier event", () => {
+        // Given we have 2 events
+        const room = createRoom();
+        const [event1] = createEvent();
+        const [event2, event2Id] = createEvent();
+        room.addLiveEvents([event1, event2]);
+
+        // When we receive a receipt for the earlier event
+        room.addReceipt(createReceipt(readerId, event1));
+
+        // Then the later one is unread
+        expect(room.hasUserReadEvent(readerId, event2Id)).toBe(false);
+    });
+
+    it("reports unread if we receive an unthreaded receipt for a different user", () => {
+        // Given my event exists and is unread
+        const room = createRoom();
+        const [event, eventId] = createEvent();
+        room.addLiveEvents([event]);
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+        // When we receive a receipt for another user
+        room.addReceipt(createReceipt(otherUserId, event));
+
+        // Then the event is still unread since the receipt was not for us
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+        // But it's read for the other person
+        expect(room.hasUserReadEvent(otherUserId, eventId)).toBe(true);
+    });
+
+    it("reports events we sent as read even if an earlier receipt arrives", () => {
+        // Given we sent an event after some other event
+        const room = createRoom();
+        const [previousEvent] = createEvent();
+        const [myEvent] = createEventSentBy(readerId);
+        room.addLiveEvents([previousEvent, myEvent]);
+
+        // And I just received a receipt for the previous event
+        room.addReceipt(createReceipt(readerId, previousEvent));
+
+        // When I ask about the event I sent, it is read (because of synthetic receipts)
+        expect(room.hasUserReadEvent(readerId, myEvent.getId()!)).toBe(true);
+    });
+
+    it("considers events after ones we sent to be unread", () => {
+        // Given we sent an event, then another event came in
+        const room = createRoom();
+        const [myEvent] = createEventSentBy(readerId);
+        const [laterEvent] = createEvent();
+        room.addLiveEvents([myEvent, laterEvent]);
+
+        // When I ask about the later event, it is unread (because it's after the synthetic receipt)
+        expect(room.hasUserReadEvent(readerId, laterEvent.getId()!)).toBe(false);
+    });
+
+    it("correctly reports readness even when receipts arrive out of order", () => {
+        // Given we have 3 events
+        const room = createRoom();
+        const [event1] = createEvent();
+        const [event2, event2Id] = createEvent();
+        const [event3, event3Id] = createEvent();
+        room.addLiveEvents([event1, event2, event3]);
+
+        // When we receive receipts for the older events out of order
+        room.addReceipt(createReceipt(readerId, event2));
+        room.addReceipt(createReceipt(readerId, event1));
+
+        // Then we correctly ignore the older receipt
+        expect(room.hasUserReadEvent(readerId, event2Id)).toBe(true);
+        expect(room.hasUserReadEvent(readerId, event3Id)).toBe(false);
+    });
+
+    it("reports read if we receive a threaded receipt for this event (main)", () => {
+        // Given my event exists and is unread
+        const room = createRoom();
+        const [event, eventId] = createEvent();
+        room.addLiveEvents([event]);
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+        // When we receive a receipt for this event+user
+        room.addReceipt(createThreadedReceipt(readerId, event, "main"));
+
+        // Then that event is read
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(true);
+    });
+
+    it("reports read if we receive a threaded receipt for this event (non-main)", () => {
+        // Given my event exists and is unread
+        const room = createRoom();
+        const [root, rootId] = createEvent();
+        const [event, eventId] = createThreadedEvent(root);
+        setupThread(room, root);
+        room.addLiveEvents([root, event]);
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+        // When we receive a receipt for this event on this thread
+        room.addReceipt(createThreadedReceipt(readerId, event, rootId));
+
+        // Then that event is read
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(true);
+    });
+
+    it("reports read if we receive an threaded receipt for a later event", () => {
+        // Given we have 2 events in a thread
+        const room = createRoom();
+        const [root, rootId] = createEvent();
+        const [event1, event1Id] = createThreadedEvent(root);
+        const [event2] = createThreadedEvent(root);
+        setupThread(room, root);
+        room.addLiveEvents([root, event1, event2]);
+
+        // When we receive a receipt for the later event
+        room.addReceipt(createThreadedReceipt(readerId, event2, rootId));
+
+        // Then the earlier one is read
+        expect(room.hasUserReadEvent(readerId, event1Id)).toBe(true);
+    });
+
+    it("reports unread if we receive an threaded receipt for an earlier event", () => {
+        // Given we have 2 events in a thread
+        const room = createRoom();
+        const [root, rootId] = createEvent();
+        const [event1] = createThreadedEvent(root);
+        const [event2, event2Id] = createThreadedEvent(root);
+        setupThread(room, root);
+        room.addLiveEvents([root, event1, event2]);
+
+        // When we receive a receipt for the earlier event
+        room.addReceipt(createThreadedReceipt(readerId, event1, rootId));
+
+        // Then the later one is unread
+        expect(room.hasUserReadEvent(readerId, event2Id)).toBe(false);
+    });
+
+    it("reports unread if we receive an threaded receipt for a different user", () => {
+        // Given my event exists and is unread
+        const room = createRoom();
+        const [root, rootId] = createEvent();
+        const [event, eventId] = createThreadedEvent(root);
+        setupThread(room, root);
+        room.addLiveEvents([root, event]);
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+        // When we receive a receipt for another user
+        room.addReceipt(createThreadedReceipt(otherUserId, event, rootId));
+
+        // Then the event is still unread since the receipt was not for us
+        expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+        // But it's read for the other person
+        expect(room.hasUserReadEvent(otherUserId, eventId)).toBe(true);
+    });
+
+    it("reports unread if we receive a receipt for a later event in a different thread", () => {
+        // Given 2 events exist in different threads
+        const room = createRoom();
+        const [root1] = createEvent();
+        const [root2] = createEvent();
+        const [thread1, thread1Id] = createThreadedEvent(root1);
+        const [thread2] = createThreadedEvent(root2);
+        setupThread(room, root1);
+        setupThread(room, root2);
+        room.addLiveEvents([root1, root2, thread1, thread2]);
+
+        // When we receive a receipt for the later event
+        room.addReceipt(createThreadedReceipt(readerId, thread2, root2.getId()!));
+
+        // Then the old one is still unread since the receipt was not for this thread
+        expect(room.hasUserReadEvent(readerId, thread1Id)).toBe(false);
+    });
+
+    it("correctly reports readness even when threaded receipts arrive out of order", () => {
+        // Given we have 3 events
+        const room = createRoom();
+        const [root, rootId] = createEvent();
+        const [event1] = createThreadedEvent(root);
+        const [event2, event2Id] = createThreadedEvent(root);
+        const [event3, event3Id] = createThreadedEvent(root);
+        setupThread(room, root);
+        room.addLiveEvents([root, event1, event2, event3]);
+
+        // When we receive receipts for the older events out of order
+        room.addReceipt(createThreadedReceipt(readerId, event2, rootId));
+        room.addReceipt(createThreadedReceipt(readerId, event1, rootId));
+
+        // Then we correctly ignore the older receipt
+        expect(room.hasUserReadEvent(readerId, event2Id)).toBe(true);
+        expect(room.hasUserReadEvent(readerId, event3Id)).toBe(false);
+    });
+
+    it("correctly reports readness when mixing threaded and unthreaded receipts", () => {
+        // Given we have a setup from this presentation:
+        // https://docs.google.com/presentation/d/1H1gxRmRFAm8d71hCILWmpOYezsvdlb7cB6ANl-20Gns/edit?usp=sharing
+        //
+        //                     Main1----\
+        //                       |       ---Thread1a <- threaded receipt
+        //                       |             |
+        //                       |          Thread1b
+        // threaded receipt -> Main2--\
+        //                       |     ----------------Thread2a <- unthreaded receipt
+        //                     Main3                      |
+        //                                             Thread2b <- threaded receipt
+        //
+        const room = createRoom();
+        const [main1, main1Id] = createEvent();
+        const [main2, main2Id] = createEvent();
+        const [main3, main3Id] = createEvent();
+        const [thread1a, thread1aId] = createThreadedEvent(main1);
+        const [thread1b, thread1bId] = createThreadedEvent(main1);
+        const [thread2a, thread2aId] = createThreadedEvent(main2);
+        const [thread2b, thread2bId] = createThreadedEvent(main2);
+        setupThread(room, main1);
+        setupThread(room, main2);
+        room.addLiveEvents([main1, thread1a, thread1b, main2, thread2a, main3, thread2b]);
+
+        // And the timestamps on the events are consistent with the order above
+        main1.event.origin_server_ts = 1;
+        thread1a.event.origin_server_ts = 2;
+        thread1b.event.origin_server_ts = 3;
+        main2.event.origin_server_ts = 4;
+        thread2a.event.origin_server_ts = 5;
+        main3.event.origin_server_ts = 6;
+        thread2b.event.origin_server_ts = 7;
+        // (Note: in principle, we have the information needed to order these
+        // events without using their timestamps, since they all came in via
+        // addLiveEvents. In reality, some of them would have come in via the
+        // /relations API, making it impossible to get the correct ordering
+        // without MSC4033, which is why we fall back to timestamps. I.e. we
+        // definitely could fix the code to make the above
+        // timestamp-manipulation unnecessary, but it would only make this test
+        // neater, not actually help in the real world.)
+
+        // When the receipts arrive
+        room.addReceipt(createThreadedReceipt(readerId, main2, "main"));
+        room.addReceipt(createThreadedReceipt(readerId, thread1a, main1Id));
+        room.addReceipt(createReceipt(readerId, thread2a));
+        room.addReceipt(createThreadedReceipt(readerId, thread2b, main2Id));
+
+        // Then we correctly identify that only main3 is unread
+        expect(room.hasUserReadEvent(readerId, main1Id)).toBe(true);
+        expect(room.hasUserReadEvent(readerId, main2Id)).toBe(true);
+        expect(room.hasUserReadEvent(readerId, main3Id)).toBe(false);
+        expect(room.hasUserReadEvent(readerId, thread1aId)).toBe(true);
+        expect(room.hasUserReadEvent(readerId, thread1bId)).toBe(true);
+        expect(room.hasUserReadEvent(readerId, thread2aId)).toBe(true);
+        expect(room.hasUserReadEvent(readerId, thread2bId)).toBe(true);
+    });
+
+    describe("dangling receipts", () => {
+        it("reports unread if the unthreaded receipt is in a dangling state", () => {
+            const room = createRoom();
+            const [event, eventId] = createEvent();
+            // When we receive a receipt for this event+user
+            room.addReceipt(createReceipt(readerId, event));
+
+            // The event is not added in the room
+            // So the receipt is in a dangling state
+            expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+            // Add the event to the room
+            // The receipt is removed from the dangling state
+            room.addLiveEvents([event]);
+
+            // Then the event is read
+            expect(room.hasUserReadEvent(readerId, eventId)).toBe(true);
+        });
+
+        it("reports unread if the threaded receipt is in a dangling state", () => {
+            const room = createRoom();
+            const [root, rootId] = createEvent();
+            const [event, eventId] = createThreadedEvent(root);
+            setupThread(room, root);
+
+            // When we receive a receipt for this event+user
+            room.addReceipt(createThreadedReceipt(readerId, event, rootId));
+
+            // The event is not added in the room
+            // So the receipt is in a dangling state
+            expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+            // Add the events to the room
+            // The receipt is removed from the dangling state
+            room.addLiveEvents([root, event]);
+
+            // Then the event is read
+            expect(room.hasUserReadEvent(readerId, eventId)).toBe(true);
+        });
+
+        it("should handle multiple dangling receipts for the same event", () => {
+            const room = createRoom();
+            const [event, eventId] = createEvent();
+            // When we receive a receipt for this event+user
+            room.addReceipt(createReceipt(readerId, event));
+            // We receive another receipt in the same event for another user
+            room.addReceipt(createReceipt(otherUserId, event));
+
+            // The event is not added in the room
+            // So the receipt is in a dangling state
+            expect(room.hasUserReadEvent(readerId, eventId)).toBe(false);
+
+            // Add the event to the room
+            // The two receipts should be processed
+            room.addLiveEvents([event]);
+
+            // Then the event is read
+            // We expect that the receipt of `otherUserId` didn't replace/erase the receipt of `readerId`
+            expect(room.hasUserReadEvent(readerId, eventId)).toBe(true);
+        });
+    });
+});
+
+function createFakeClient(): MatrixClient {
+    return {
+        getUserId: jest.fn(),
+        getEventMapper: jest.fn().mockReturnValue(jest.fn()),
+        isInitialSyncComplete: jest.fn().mockReturnValue(true),
+        supportsThreads: jest.fn().mockReturnValue(true),
+        fetchRoomEvent: jest.fn().mockResolvedValue({}),
+        paginateEventTimeline: jest.fn(),
+        canSupport: { get: jest.fn() },
+    } as unknown as MatrixClient;
+}
+
+const senderId = "sender:s.ss";
+const readerId = "reader:r.rr";
+const otherUserId = "other:o.oo";
+
+function createRoom(): Room {
+    return new Room("!rid", createFakeClient(), "@u:s.nz", { timelineSupport: true });
+}
+
+let idCounter = 0;
+function nextId(): string {
+    return "$" + (idCounter++).toString(10);
+}
+
+/**
+ * Create an event and return it and its ID.
+ */
+function createEvent(): [MatrixEvent, string] {
+    return createEventSentBy(senderId);
+}
+
+/**
+ * Create an event with the supplied sender and return it and its ID.
+ */
+function createEventSentBy(customSenderId: string): [MatrixEvent, string] {
+    const event = new MatrixEvent({ sender: customSenderId, event_id: nextId() });
+    return [event, event.getId()!];
+}
+
+/**
+ * Create an event in the thread of the supplied root and return it and its ID.
+ */
+function createThreadedEvent(root: MatrixEvent): [MatrixEvent, string] {
+    const rootEventId = root.getId()!;
+    const event = new MatrixEvent({
+        sender: senderId,
+        event_id: nextId(),
+        content: {
+            "m.relates_to": {
+                event_id: rootEventId,
+                rel_type: THREAD_RELATION_TYPE.name,
+                ["m.in_reply_to"]: {
+                    event_id: rootEventId,
+                },
+            },
+        },
+    });
+    return [event, event.getId()!];
+}
+
+function createReceipt(userId: string, referencedEvent: MatrixEvent): MatrixEvent {
+    const content: ReceiptContent = {
+        [referencedEvent.getId()!]: {
+            "m.read": {
+                [userId]: {
+                    ts: 123,
+                },
+            },
+        },
+    };
+
+    return new MatrixEvent({
+        type: "m.receipt",
+        content,
+    });
+}
+
+function createThreadedReceipt(userId: string, referencedEvent: MatrixEvent, threadId: string): MatrixEvent {
+    const content: ReceiptContent = {
+        [referencedEvent.getId()!]: {
+            "m.read": {
+                [userId]: {
+                    ts: 123,
+                    thread_id: threadId,
+                },
+            },
+        },
+    };
+
+    return new MatrixEvent({
+        type: "m.receipt",
+        content,
+    });
+}
+
+/**
+ * Create a timeline in the timeline set that is not the live timeline.
+ */
+function createOldTimeline(room: Room, events: MatrixEvent[]) {
+    const oldTimeline = room.getUnfilteredTimelineSet().addTimeline();
+    room.getUnfilteredTimelineSet().addEventsToTimeline(events, true, oldTimeline);
+}
+
+/**
+ * Perform the hacks required for this room to create a thread based on the root
+ * event supplied.
+ */
+function setupThread(room: Room, root: MatrixEvent) {
+    const thread = room.createThread(root.getId()!, root, [root], false);
+    thread.initialEventsFetched = true;
+}
@@ -19,7 +19,7 @@ import { mocked } from "jest-mock";
 import { MatrixClient, PendingEventOrdering } from "../../../src/client";
 import { Room, RoomEvent } from "../../../src/models/room";
 import { FeatureSupport, Thread, THREAD_RELATION_TYPE, ThreadEvent } from "../../../src/models/thread";
-import { makeThreadEvent, mkThread } from "../../test-utils/thread";
+import { makeThreadEvent, mkThread, populateThread } from "../../test-utils/thread";
 import { TestClient } from "../../TestClient";
 import { emitPromise, mkEdit, mkMessage, mkReaction, mock } from "../../test-utils/test-utils";
 import { Direction, EventStatus, EventType, MatrixEvent } from "../../../src";
@@ -149,20 +149,38 @@ describe("Thread", () => {
        });

        it("considers other events with no RR as unread", () => {
-            const { thread, events } = mkThread({
+            // Given a long thread exists
+            const { thread, events } = populateThread({
                room,
                client,
-                authorId: myUserId,
-                participantUserIds: [myUserId],
+                authorId: "@other:foo.com",
+                participantUserIds: ["@other:foo.com"],
                length: 25,
                ts: 190,
            });

-            // Before alice's last unthreaded receipt
-            expect(thread.hasUserReadEvent("@alice:example.org", events.at(1)!.getId() ?? "")).toBeTruthy();
+            const event1 = events.at(1)!;
+            const event2 = events.at(2)!;
+            const event24 = events.at(24)!;

-            // After alice's last unthreaded receipt
-            expect(thread.hasUserReadEvent("@alice:example.org", events.at(-1)!.getId() ?? "")).toBeFalsy();
+            // And we have read the second message in it with an unthreaded receipt
+            const receipt = new MatrixEvent({
+                type: "m.receipt",
+                room_id: room.roomId,
+                content: {
+                    // unthreaded receipt for the second message in the thread
+                    [event2.getId()!]: {
+                        [ReceiptType.Read]: {
+                            [myUserId]: { ts: 200 },
+                        },
+                    },
+                },
+            });
+            room.addReceipt(receipt);
+
+            // Then we have read the first message in the thread, and not the last
+            expect(thread.hasUserReadEvent(myUserId, event1.getId()!)).toBe(true);
+            expect(thread.hasUserReadEvent(myUserId, event24.getId()!)).toBe(false);
        });

        it("considers event as read if there's a more recent unthreaded receipt", () => {
@@ -481,13 +499,13 @@ describe("Thread", () => {

                // And a thread with an added event (with later timestamp)
                const userId = "user1";
-                const { thread, message } = await createThreadAndEvent(client, 1, 100, userId);
+                const { thread, message2 } = await createThreadAnd2Events(client, 1, 100, 200, userId);

                // Then a receipt was added to the thread
                const receipt = thread.getReadReceiptForUserId(userId);
                expect(receipt).toBeTruthy();
-                expect(receipt?.eventId).toEqual(message.getId());
-                expect(receipt?.data.ts).toEqual(100);
+                expect(receipt?.eventId).toEqual(message2.getId());
+                expect(receipt?.data.ts).toEqual(200);
                expect(receipt?.data.thread_id).toEqual(thread.id);

                // (And the receipt was synthetic)
@@ -505,14 +523,14 @@ describe("Thread", () => {

                // And a thread with an added event with a lower timestamp than its other events
                const userId = "user1";
-                const { thread } = await createThreadAndEvent(client, 200, 100, userId);
+                const { thread, message1 } = await createThreadAnd2Events(client, 300, 200, 100, userId);

-                // Then no receipt was added to the thread (the receipt is still
-                // for the thread root). This happens because since we have no
+                // Then the receipt is for the first message, because its
+                // timestamp is later. This happens because since we have no
                // recursive relations support, we know that sometimes events
                // appear out of order, so we have to check their timestamps as
                // a guess of the correct order.
-                expect(thread.getReadReceiptForUserId(userId)?.eventId).toEqual(thread.rootEvent?.getId());
+                expect(thread.getReadReceiptForUserId(userId)?.eventId).toEqual(message1.getId());
            });
        });

@@ -530,11 +548,11 @@ describe("Thread", () => {

                // And a thread with an added event (with later timestamp)
                const userId = "user1";
-                const { thread, message } = await createThreadAndEvent(client, 1, 100, userId);
+                const { thread, message2 } = await createThreadAnd2Events(client, 1, 100, 200, userId);

                // Then a receipt was added to the thread
                const receipt = thread.getReadReceiptForUserId(userId);
-                expect(receipt?.eventId).toEqual(message.getId());
+                expect(receipt?.eventId).toEqual(message2.getId());
            });

            it("Creates a local echo receipt even for events BEFORE an existing receipt", async () => {
@@ -550,22 +568,24 @@ describe("Thread", () => {

                // And a thread with an added event with a lower timestamp than its other events
                const userId = "user1";
-                const { thread, message } = await createThreadAndEvent(client, 200, 100, userId);
+                const { thread, message2 } = await createThreadAnd2Events(client, 300, 200, 100, userId);

-                // Then a receipt was added to the thread, because relations
-                // recursion is available, so we trust the server to have
-                // provided us with events in the right order.
+                // Then a receipt was added for the last message, even though it
+                // has lower ts, because relations recursion is available, so we
+                // trust the server to have provided us with events in the right
+                // order.
                const receipt = thread.getReadReceiptForUserId(userId);
-                expect(receipt?.eventId).toEqual(message.getId());
+                expect(receipt?.eventId).toEqual(message2.getId());
            });
        });

-        async function createThreadAndEvent(
+        async function createThreadAnd2Events(
            client: MatrixClient,
            rootTs: number,
-            eventTs: number,
+            message1Ts: number,
+            message2Ts: number,
            userId: string,
-        ): Promise<{ thread: Thread; message: MatrixEvent }> {
+        ): Promise<{ thread: Thread; message1: MatrixEvent; message2: MatrixEvent }> {
            const room = new Room("room1", client, userId);

            // Given a thread
@@ -576,24 +596,41 @@ describe("Thread", () => {
                participantUserIds: [],
                ts: rootTs,
            });
-            // Sanity: the current receipt is for the thread root
-            expect(thread.getReadReceiptForUserId(userId)?.eventId).toEqual(thread.rootEvent?.getId());
+            // Sanity: there is no read receipt on the thread yet because the
+            // thread events don't get properly added to the room by mkThread.
+            expect(thread.getReadReceiptForUserId(userId)).toBeNull();

            const awaitTimelineEvent = new Promise<void>((res) => thread.on(RoomEvent.Timeline, () => res()));

-            // When we add a message that is before the latest receipt
-            const message = makeThreadEvent({
+            // Add a message with ts message1Ts
+            const message1 = makeThreadEvent({
                event: true,
                rootEventId: thread.id,
                replyToEventId: thread.id,
                user: userId,
                room: room.roomId,
-                ts: eventTs,
+                ts: message1Ts,
            });
-            await thread.addEvent(message, false, true);
+            await thread.addEvent(message1, false, true);
            await awaitTimelineEvent;

-            return { thread, message };
+            // Sanity: the thread now has a properly-added event, so this event
+            // has a synthetic receipt.
+            expect(thread.getReadReceiptForUserId(userId)?.eventId).toEqual(message1.getId());
+
+            // Add a message with ts message2Ts
+            const message2 = makeThreadEvent({
+                event: true,
+                rootEventId: thread.id,
+                replyToEventId: thread.id,
+                user: userId,
+                room: room.roomId,
+                ts: message2Ts,
+            });
+            await thread.addEvent(message2, false, true);
+            await awaitTimelineEvent;
+
+            return { thread, message1, message2 };
        }

        function createClientWithEventMapper(canSupport: Map<Feature, ServerSupport> = new Map()): MatrixClient {
@@ -675,6 +712,69 @@ describe("Thread", () => {
            });
        });
    });
+
+    describe("addEvent", () => {
+        describe("Given server support for threads", () => {
+            let previousThreadHasServerSideSupport: FeatureSupport;
+
+            beforeAll(() => {
+                previousThreadHasServerSideSupport = Thread.hasServerSideSupport;
+                Thread.hasServerSideSupport = FeatureSupport.Stable;
+            });
+
+            afterAll(() => {
+                Thread.hasServerSideSupport = previousThreadHasServerSideSupport;
+            });
+
+            it("Adds events even if they appear out of order", async () => {
+                // Given a thread exists
+                const client = createClient();
+                const user = "@alice:matrix.org";
+                const room = "!room:z";
+                const thread = await createThread(client, user, room);
+                const prevNumEvents = thread.timeline.length;
+
+                // When two messages come in but the later one has an older timestamp
+                const message1 = createThreadMessage(thread.id, user, room, "message1");
+                const message2 = createThreadMessage(thread.id, user, room, "message2");
+                message2.localTimestamp -= 10000;
+
+                await thread.addEvent(message1, false);
+                await thread.addEvent(message2, false);
+
+                // Then both events end up in the timeline
+                expect(thread.timeline.length - prevNumEvents).toEqual(2);
+                const lastEvent = thread.timeline.at(-1)!;
+                const secondLastEvent = thread.timeline.at(-2)!;
+                expect(lastEvent).toBe(message2);
+                expect(secondLastEvent).toBe(message1);
+            });
+
+            it("Adds events to start even if they appear out of order", async () => {
+                // Given a thread exists
+                const client = createClient();
+                const user = "@alice:matrix.org";
+                const room = "!room:z";
+                const thread = await createThread(client, user, room);
+                const prevNumEvents = thread.timeline.length;
+
+                // When two messages come in but the later one has an older timestamp
+                const message1 = createThreadMessage(thread.id, user, room, "message1");
+                const message2 = createThreadMessage(thread.id, user, room, "message2");
+                message2.localTimestamp -= 10000;
+
+                await thread.addEvent(message1, false);
+                await thread.addEvent(message2, true);
+
+                // Then both events end up in the timeline
+                expect(thread.timeline.length - prevNumEvents).toEqual(2);
+                const lastEvent = thread.timeline.at(-1)!;
+                const firstEvent = thread.timeline.at(0)!;
+                expect(lastEvent).toBe(message1);
+                expect(firstEvent).toBe(message2);
+            });
+        });
+    });
 });

 /**
@@ -106,6 +106,8 @@ describe("fixNotificationCountOnDecryption", () => {
            mockClient,
        );

+        room.addLiveEvents([event]);
+
        THREAD_ID = event.getId()!;
        threadEvent = mkEvent({
            type: EventType.RoomMessage,
@@ -134,6 +134,25 @@ describe("oidc authorization", () => {

            expect(authUrl.searchParams.get("code_challenge")).toBeTruthy();
        });
+
+        it("should generate url with create prompt", async () => {
+            const nonce = "abc123";
+
+            const metadata = delegatedAuthConfig.metadata;
+
+            const authUrl = new URL(
+                await generateOidcAuthorizationUrl({
+                    metadata,
+                    homeserverUrl: baseUrl,
+                    clientId,
+                    redirectUri: baseUrl,
+                    nonce,
+                    prompt: "create",
+                }),
+            );
+
+            expect(authUrl.searchParams.get("prompt")).toEqual("create");
+        });
    });

    describe("completeAuthorizationCodeGrant", () => {
@@ -284,6 +303,7 @@ describe("oidc authorization", () => {
                    expires_at: result.tokenResponse.expires_at,
                    scope,
                },
+                idTokenClaims: result.idTokenClaims,
            });
        });

@@ -325,6 +345,7 @@ describe("oidc authorization", () => {
                    expires_at: result.tokenResponse.expires_at,
                    scope,
                },
+                idTokenClaims: result.idTokenClaims,
            });

            expect(result.tokenResponse.token_type).toEqual("Bearer");
@@ -0,0 +1,270 @@
+/**
+ * @jest-environment jsdom
+ */
+
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import fetchMock from "fetch-mock-jest";
+
+import { OidcTokenRefresher } from "../../../src";
+import { logger } from "../../../src/logger";
+import { makeDelegatedAuthConfig } from "../../test-utils/oidc";
+
+describe("OidcTokenRefresher", () => {
+    // OidcTokenRefresher props
+    // see class declaration for info
+    const authConfig = {
+        issuer: "https://issuer.org/",
+    };
+    const clientId = "test-client-id";
+    const redirectUri = "https://test.org";
+    const deviceId = "abc123";
+    const idTokenClaims = {
+        exp: Date.now() / 1000 + 100000,
+        aud: clientId,
+        iss: authConfig.issuer,
+        sub: "123",
+        iat: 123,
+    };
+    // used to mock a valid token response, as consumed by OidcClient library
+    const scope = `openid urn:matrix:org.matrix.msc2967.client:api:* urn:matrix:org.matrix.msc2967.client:device:${deviceId}`;
+
+    // auth config used in mocked calls to OP .well-known
+    const config = makeDelegatedAuthConfig(authConfig.issuer);
+
+    const makeTokenResponse = (accessToken: string, refreshToken?: string) => ({
+        access_token: accessToken,
+        refresh_token: refreshToken,
+        token_type: "Bearer",
+        expires_in: 300,
+        scope: scope,
+    });
+
+    beforeEach(() => {
+        fetchMock.get(`${config.metadata.issuer}.well-known/openid-configuration`, config.metadata);
+        fetchMock.get(`${config.metadata.issuer}jwks`, {
+            status: 200,
+            headers: {
+                "Content-Type": "application/json",
+            },
+            keys: [],
+        });
+
+        fetchMock.post(config.metadata.token_endpoint, {
+            status: 200,
+            headers: {
+                "Content-Type": "application/json",
+            },
+            ...makeTokenResponse("new-access-token", "new-refresh-token"),
+        });
+    });
+
+    afterEach(() => {
+        jest.restoreAllMocks();
+        fetchMock.resetBehavior();
+    });
+
+    it("throws when oidc client cannot be initialised", async () => {
+        jest.spyOn(logger, "error");
+        fetchMock.get(
+            `${config.metadata.issuer}.well-known/openid-configuration`,
+            {
+                ok: false,
+                status: 404,
+            },
+            { overwriteRoutes: true },
+        );
+        const refresher = new OidcTokenRefresher(authConfig, clientId, redirectUri, deviceId, idTokenClaims);
+        await expect(refresher.oidcClientReady).rejects.toThrow();
+        expect(logger.error).toHaveBeenCalledWith(
+            "Failed to initialise OIDC client.",
+            // error from OidcClient
+            expect.any(Error),
+        );
+    });
+
+    it("initialises oidc client", async () => {
+        const refresher = new OidcTokenRefresher(authConfig, clientId, redirectUri, deviceId, idTokenClaims);
+        await refresher.oidcClientReady;
+
+        // @ts-ignore peek at private property to see we initialised the client correctly
+        expect(refresher.oidcClient.settings).toEqual(
+            expect.objectContaining({
+                client_id: clientId,
+                redirect_uri: redirectUri,
+                authority: authConfig.issuer,
+                scope,
+            }),
+        );
+    });
+
+    describe("doRefreshAccessToken()", () => {
+        it("should throw when oidcClient has not been initialised", async () => {
+            const refresher = new OidcTokenRefresher(authConfig, clientId, redirectUri, deviceId, idTokenClaims);
+            await expect(refresher.doRefreshAccessToken("token")).rejects.toThrow(
+                "Cannot get new token before OIDC client is initialised.",
+            );
+        });
+
+        it("should refresh the tokens", async () => {
+            const refresher = new OidcTokenRefresher(authConfig, clientId, redirectUri, deviceId, idTokenClaims);
+            await refresher.oidcClientReady;
+
+            const result = await refresher.doRefreshAccessToken("refresh-token");
+
+            expect(fetchMock).toHaveFetched(config.metadata.token_endpoint, {
+                method: "POST",
+            });
+
+            expect(result).toEqual({
+                accessToken: "new-access-token",
+                refreshToken: "new-refresh-token",
+            });
+        });
+
+        it("should persist the new tokens", async () => {
+            const refresher = new OidcTokenRefresher(authConfig, clientId, redirectUri, deviceId, idTokenClaims);
+            await refresher.oidcClientReady;
+            // spy on our stub
+            jest.spyOn(refresher, "persistTokens");
+
+            await refresher.doRefreshAccessToken("refresh-token");
+
+            expect(refresher.persistTokens).toHaveBeenCalledWith({
+                accessToken: "new-access-token",
+                refreshToken: "new-refresh-token",
+            });
+        });
+
+        it("should only have one inflight refresh request at once", async () => {
+            fetchMock
+                .postOnce(
+                    config.metadata.token_endpoint,
+                    {
+                        status: 200,
+                        headers: {
+                            "Content-Type": "application/json",
+                        },
+                        ...makeTokenResponse("first-new-access-token", "first-new-refresh-token"),
+                    },
+                    { overwriteRoutes: true },
+                )
+                .postOnce(
+                    config.metadata.token_endpoint,
+                    {
+                        status: 200,
+                        headers: {
+                            "Content-Type": "application/json",
+                        },
+                        ...makeTokenResponse("second-new-access-token", "second-new-refresh-token"),
+                    },
+                    { overwriteRoutes: false },
+                );
+
+            const refresher = new OidcTokenRefresher(authConfig, clientId, redirectUri, deviceId, idTokenClaims);
+            await refresher.oidcClientReady;
+            // reset call counts
+            fetchMock.resetHistory();
+
+            const refreshToken = "refresh-token";
+            const first = refresher.doRefreshAccessToken(refreshToken);
+            const second = refresher.doRefreshAccessToken(refreshToken);
+
+            const result1 = await second;
+            const result2 = await first;
+
+            // only one call to token endpoint
+            expect(fetchMock).toHaveFetchedTimes(1, config.metadata.token_endpoint);
+            expect(result1).toEqual({
+                accessToken: "first-new-access-token",
+                refreshToken: "first-new-refresh-token",
+            });
+            // same response
+            expect(result1).toEqual(result2);
+
+            // call again after first request resolves
+            const third = await refresher.doRefreshAccessToken("first-new-refresh-token");
+
+            // called token endpoint, got new tokens
+            expect(third).toEqual({
+                accessToken: "second-new-access-token",
+                refreshToken: "second-new-refresh-token",
+            });
+        });
+
+        it("should log and rethrow when token refresh fails", async () => {
+            fetchMock.post(
+                config.metadata.token_endpoint,
+                {
+                    status: 503,
+                    headers: {
+                        "Content-Type": "application/json",
+                    },
+                },
+                { overwriteRoutes: true },
+            );
+
+            const refresher = new OidcTokenRefresher(authConfig, clientId, redirectUri, deviceId, idTokenClaims);
+            await refresher.oidcClientReady;
+
+            await expect(refresher.doRefreshAccessToken("refresh-token")).rejects.toThrow();
+        });
+
+        it("should make fresh request after a failed request", async () => {
+            // make sure inflight request is cleared after a failure
+            fetchMock
+                .postOnce(
+                    config.metadata.token_endpoint,
+                    {
+                        status: 503,
+                        headers: {
+                            "Content-Type": "application/json",
+                        },
+                    },
+                    { overwriteRoutes: true },
+                )
+                .postOnce(
+                    config.metadata.token_endpoint,
+                    {
+                        status: 200,
+                        headers: {
+                            "Content-Type": "application/json",
+                        },
+                        ...makeTokenResponse("second-new-access-token", "second-new-refresh-token"),
+                    },
+                    { overwriteRoutes: false },
+                );
+
+            const refresher = new OidcTokenRefresher(authConfig, clientId, redirectUri, deviceId, idTokenClaims);
+            await refresher.oidcClientReady;
+            // reset call counts
+            fetchMock.resetHistory();
+
+            // first call fails
+            await expect(refresher.doRefreshAccessToken("refresh-token")).rejects.toThrow();
+
+            // call again after first request resolves
+            const result = await refresher.doRefreshAccessToken("first-new-refresh-token");
+
+            // called token endpoint, got new tokens
+            expect(result).toEqual({
+                accessToken: "second-new-access-token",
+                refreshToken: "second-new-refresh-token",
+            });
+        });
+    });
+});
@@ -0,0 +1,66 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { decodeBase64 } from "../../src/base64";
+import {
+    randomLowercaseString,
+    randomString,
+    randomUppercaseString,
+    secureRandomBase64Url,
+} from "../../src/randomstring";
+
+describe("Random strings", () => {
+    it.each([8, 16, 32])("secureRandomBase64 generates %i valid base64 bytes", (n: number) => {
+        const randb641 = secureRandomBase64Url(n);
+        const randb642 = secureRandomBase64Url(n);
+
+        expect(randb641).not.toEqual(randb642);
+
+        const decoded = decodeBase64(randb641);
+        expect(decoded).toHaveLength(n);
+    });
+
+    it.each([8, 16, 32])("randomString generates string of %i characters", (n: number) => {
+        const rand1 = randomString(n);
+        const rand2 = randomString(n);
+
+        expect(rand1).not.toEqual(rand2);
+
+        expect(rand1).toHaveLength(n);
+    });
+
+    it.each([8, 16, 32])("randomLowercaseString generates lowercase string of %i characters", (n: number) => {
+        const rand1 = randomLowercaseString(n);
+        const rand2 = randomLowercaseString(n);
+
+        expect(rand1).not.toEqual(rand2);
+
+        expect(rand1).toHaveLength(n);
+
+        expect(rand1.toLowerCase()).toEqual(rand1);
+    });
+
+    it.each([8, 16, 32])("randomUppercaseString generates lowercase string of %i characters", (n: number) => {
+        const rand1 = randomUppercaseString(n);
+        const rand2 = randomUppercaseString(n);
+
+        expect(rand1).not.toEqual(rand2);
+
+        expect(rand1).toHaveLength(n);
+
+        expect(rand1.toUpperCase()).toEqual(rand1);
+    });
+});
@@ -18,7 +18,7 @@ import MockHttpBackend from "matrix-mock-request";

 import { MAIN_ROOM_TIMELINE, ReceiptType, WrappedReceipt } from "../../src/@types/read_receipts";
 import { MatrixClient } from "../../src/client";
-import { EventType, MatrixEvent, Room } from "../../src/matrix";
+import { EventType, MatrixEvent, RelationType, Room, threadIdForReceipt } from "../../src/matrix";
 import { synthesizeReceipt } from "../../src/models/read-receipt";
 import { encodeUri } from "../../src/utils";
 import * as utils from "../test-utils/test-utils";
@@ -43,8 +43,10 @@ const THREAD_ID = "$thread_event_id";
 const ROOM_ID = "!123:matrix.org";

 describe("Read receipt", () => {
+    let threadRoot: MatrixEvent;
    let threadEvent: MatrixEvent;
    let roomEvent: MatrixEvent;
+    let editOfThreadRoot: MatrixEvent;

    beforeEach(() => {
        httpBackend = new MockHttpBackend();
@@ -57,6 +59,15 @@ describe("Read receipt", () => {
        client.isGuest = () => false;
        client.supportsThreads = () => true;

+        threadRoot = utils.mkEvent({
+            event: true,
+            type: EventType.RoomMessage,
+            user: "@bob:matrix.org",
+            room: ROOM_ID,
+            content: { body: "This is the thread root" },
+        });
+        threadRoot.event.event_id = THREAD_ID;
+
        threadEvent = utils.mkEvent({
            event: true,
            type: EventType.RoomMessage,
@@ -82,6 +93,9 @@ describe("Read receipt", () => {
                body: "Hello from a room",
            },
        });
+
+        editOfThreadRoot = utils.mkEdit(threadRoot, client, "@bob:matrix.org", ROOM_ID);
+        editOfThreadRoot.setThreadId(THREAD_ID);
    });

    describe("sendReceipt", () => {
@@ -208,6 +222,7 @@ describe("Read receipt", () => {
        it.each([
            { getEvent: () => roomEvent, destinationId: MAIN_ROOM_TIMELINE },
            { getEvent: () => threadEvent, destinationId: THREAD_ID },
+            { getEvent: () => editOfThreadRoot, destinationId: MAIN_ROOM_TIMELINE },
        ])("adds the receipt to $destinationId", ({ getEvent, destinationId }) => {
            const event = getEvent();
            const userId = "@bob:example.org";
@@ -225,6 +240,7 @@ describe("Read receipt", () => {
        it("should not allow an older unthreaded receipt to clobber a `main` threaded one", () => {
            const userId = client.getSafeUserId();
            const room = new Room(ROOM_ID, client, userId);
+            room.findEventById = jest.fn().mockReturnValue({} as MatrixEvent);

            const unthreadedReceipt: WrappedReceipt = {
                eventId: "$olderEvent",
@@ -258,4 +274,200 @@ describe("Read receipt", () => {
            expect(room.getEventReadUpTo(userId)).toBe(mainTimelineReceipt.eventId);
        });
    });
+
+    describe("Determining the right thread ID for a receipt", () => {
+        it("provides the thread root ID for a normal threaded message", () => {
+            const event = utils.mkEvent({
+                event: true,
+                type: EventType.RoomMessage,
+                user: "@bob:matrix.org",
+                room: "!roomx",
+                content: {
+                    "body": "Hello from a thread",
+                    "m.relates_to": {
+                        "event_id": "$thread1",
+                        "m.in_reply_to": {
+                            event_id: "$thread1",
+                        },
+                        "rel_type": "m.thread",
+                    },
+                },
+            });
+
+            expect(threadIdForReceipt(event)).toEqual("$thread1");
+        });
+
+        it("provides 'main' for a non-thread message", () => {
+            const event = utils.mkEvent({
+                event: true,
+                type: EventType.RoomMessage,
+                user: "@bob:matrix.org",
+                room: "!roomx",
+                content: { body: "Hello" },
+            });
+
+            expect(threadIdForReceipt(event)).toEqual("main");
+        });
+
+        it("provides 'main' for a thread root", () => {
+            const event = utils.mkEvent({
+                event: true,
+                type: EventType.RoomMessage,
+                user: "@bob:matrix.org",
+                room: "!roomx",
+                content: { body: "Hello" },
+            });
+            // Set thread ID to this event's ID, meaning this is the thread root
+            event.setThreadId(event.getId());
+
+            expect(threadIdForReceipt(event)).toEqual("main");
+        });
+
+        it("provides 'main' for a reaction to a thread root", () => {
+            const event = utils.mkEvent({
+                event: true,
+                type: EventType.Reaction,
+                user: "@bob:matrix.org",
+                room: "!roomx",
+                content: {
+                    "m.relates_to": {
+                        rel_type: RelationType.Annotation,
+                        event_id: "$thread1",
+                        key: Math.random().toString(),
+                    },
+                },
+            });
+
+            // Set thread Id, meaning this looks like it's in the thread (this
+            // happens for relations like this, so that they appear in the
+            // thread's timeline).
+            event.setThreadId("$thread1");
+
+            // But because it's a reaction to the thread root, it's in main
+            expect(threadIdForReceipt(event)).toEqual("main");
+        });
+
+        it("provides the thread ID for a reaction to a threaded message", () => {
+            const event = utils.mkEvent({
+                event: true,
+                type: EventType.Reaction,
+                user: "@bob:matrix.org",
+                room: "!roomx",
+                content: {
+                    "m.relates_to": {
+                        rel_type: RelationType.Annotation,
+                        event_id: "$withinthread2",
+                        key: Math.random().toString(),
+                    },
+                },
+            });
+
+            // Set thread Id, to say this message is in the thread. This happens
+            // when the message arrived and is classified.
+            event.setThreadId("$thread1");
+
+            // It's in the thread because it refers to something else, not the
+            // thread root
+            expect(threadIdForReceipt(event)).toEqual("$thread1");
+        });
+
+        it("(suprisingly?) provides 'main' for a redaction of a threaded message", () => {
+            const event = utils.mkEvent({
+                event: true,
+                type: EventType.RoomRedaction,
+                content: {
+                    reason: "Spamming",
+                },
+                redacts: "$withinthread2",
+                room: "!roomx",
+                user: "@bob:matrix.org",
+            });
+
+            // Set thread Id, to say this message is in the thread.
+            event.setThreadId("$thread1");
+
+            // Because redacting a message removes all its m.relations, the
+            // message is no longer in the thread, so we must send a receipt for
+            // it in the main timeline.
+            //
+            // This is surprising, but it follows the spec (at least up to
+            // current latest room version, 11). In fact, the event should no
+            // longer have a thread ID set on it, so this testcase should not
+            // come up. (At time of writing, this is not the case though - it
+            // does still have threadId set.)
+            expect(threadIdForReceipt(event)).toEqual("main");
+        });
+
+        it("provides the thread ID for an edit of a threaded message", () => {
+            const event = utils.mkEvent({
+                event: true,
+                type: EventType.RoomRedaction,
+                content: {
+                    "body": "Edited!",
+                    "m.new_content": {
+                        body: "Edited!",
+                    },
+                    "m.relates_to": {
+                        rel_type: RelationType.Replace,
+                        event_id: "$withinthread2",
+                    },
+                },
+                room: "!roomx",
+                user: "@bob:matrix.org",
+            });
+
+            // Set thread Id, to say this message is in the thread.
+            event.setThreadId("$thread1");
+
+            // It's in the thread, because it redacts something inside the
+            // thread (not the thread root)
+            expect(threadIdForReceipt(event)).toEqual("$thread1");
+        });
+
+        it("provides 'main' for an edit of a thread root", () => {
+            const event = utils.mkEvent({
+                event: true,
+                type: EventType.RoomRedaction,
+                content: {
+                    "body": "Edited!",
+                    "m.new_content": {
+                        body: "Edited!",
+                    },
+                    "m.relates_to": {
+                        rel_type: RelationType.Replace,
+                        event_id: "$thread1",
+                    },
+                },
+                room: "!roomx",
+                user: "@bob:matrix.org",
+            });
+
+            // Set thread Id, to say this message is in the thread.
+            event.setThreadId("$thread1");
+
+            // It's in the thread, because it redacts something inside the
+            // thread (not the thread root)
+            expect(threadIdForReceipt(event)).toEqual("main");
+        });
+
+        it("provides 'main' for a redaction of the thread root", () => {
+            const event = utils.mkEvent({
+                event: true,
+                type: EventType.RoomRedaction,
+                content: {
+                    reason: "Spamming",
+                },
+                redacts: "$thread1",
+                room: "!roomx",
+                user: "@bob:matrix.org",
+            });
+
+            // Set thread Id, to say this message is in the thread.
+            event.setThreadId("$thread1");
+
+            // It's in the thread, because it redacts something inside the
+            // thread (not the thread root)
+            expect(threadIdForReceipt(event)).toEqual("main");
+        });
+    });
 });
@@ -32,7 +32,10 @@ export class DummyTransport<D extends RendezvousTransportDetails, T> implements
    ready = false;
    cancelled = false;

-    constructor(private name: string, private mockDetails: D) {}
+    constructor(
+        private name: string,
+        private mockDetails: D,
+    ) {}
    onCancelled?: RendezvousFailureListener;

    details(): Promise<RendezvousTransportDetails> {
@@ -17,7 +17,7 @@ limitations under the License.
 import "../../olm-loader";
 import { RendezvousFailureReason, RendezvousIntent } from "../../../src/rendezvous";
 import { MSC3903ECDHPayload, MSC3903ECDHv2RendezvousChannel } from "../../../src/rendezvous/channels";
-import { decodeBase64 } from "../../../src/crypto/olmlib";
+import { decodeBase64 } from "../../../src/base64";
 import { DummyTransport } from "./DummyTransport";

 function makeTransport(name: string) {
@@ -29,7 +29,7 @@ import {
    MSC3886SimpleHttpRendezvousTransportDetails,
 } from "../../../src/rendezvous/transports";
 import { DummyTransport } from "./DummyTransport";
-import { decodeBase64 } from "../../../src/crypto/olmlib";
+import { decodeBase64 } from "../../../src/base64";
 import { logger } from "../../../src/logger";
 import { DeviceInfo } from "../../../src/crypto/deviceinfo";

@@ -37,7 +37,7 @@ function makeMockClient(opts: {
    userId: string;
    deviceId: string;
    deviceKey?: string;
-    msc3882Enabled: boolean;
+    getLoginTokenEnabled: boolean;
    msc3882r0Only: boolean;
    msc3886Enabled: boolean;
    devices?: Record<string, Partial<DeviceInfo>>;
@@ -54,7 +54,7 @@ function makeMockClient(opts: {
        getVersions() {
            return {
                unstable_features: {
-                    "org.matrix.msc3882": opts.msc3882Enabled,
+                    "org.matrix.msc3882": opts.getLoginTokenEnabled,
                    "org.matrix.msc3886": opts.msc3886Enabled,
                },
            };
@@ -64,8 +64,8 @@ function makeMockClient(opts: {
                ? {}
                : {
                      capabilities: {
-                          "org.matrix.msc3882.get_login_token": {
-                              enabled: opts.msc3882Enabled,
+                          "m.get_login_token": {
+                              enabled: opts.getLoginTokenEnabled,
                          },
                      },
                  };
@@ -122,7 +122,7 @@ describe("Rendezvous", function () {
            userId: "@alice:example.com",
            deviceId: "DEVICEID",
            msc3886Enabled: false,
-            msc3882Enabled: true,
+            getLoginTokenEnabled: true,
            msc3882r0Only: true,
        });
        httpBackend.when("POST", "https://fallbackserver/rz").response = {
@@ -180,10 +180,10 @@ describe("Rendezvous", function () {
    });

    async function testNoProtocols({
-        msc3882Enabled,
+        getLoginTokenEnabled,
        msc3882r0Only,
    }: {
-        msc3882Enabled: boolean;
+        getLoginTokenEnabled: boolean;
        msc3882r0Only: boolean;
    }) {
        const aliceTransport = makeTransport("Alice");
@@ -198,7 +198,7 @@ describe("Rendezvous", function () {
            userId: "alice",
            deviceId: "ALICE",
            msc3886Enabled: false,
-            msc3882Enabled,
+            getLoginTokenEnabled,
            msc3882r0Only,
        });
        const aliceEcdh = new MSC3903ECDHRendezvousChannel(aliceTransport, undefined, aliceOnFailure);
@@ -241,11 +241,11 @@ describe("Rendezvous", function () {
    }

    it("no protocols - r0", async function () {
-        await testNoProtocols({ msc3882Enabled: false, msc3882r0Only: true });
+        await testNoProtocols({ getLoginTokenEnabled: false, msc3882r0Only: true });
    });

-    it("no protocols - r1", async function () {
-        await testNoProtocols({ msc3882Enabled: false, msc3882r0Only: false });
+    it("no protocols - stable", async function () {
+        await testNoProtocols({ getLoginTokenEnabled: false, msc3882r0Only: false });
    });

    it("new device declines protocol with outcome unsupported", async function () {
@@ -260,7 +260,7 @@ describe("Rendezvous", function () {
        const alice = makeMockClient({
            userId: "alice",
            deviceId: "ALICE",
-            msc3882Enabled: true,
+            getLoginTokenEnabled: true,
            msc3882r0Only: false,
            msc3886Enabled: false,
        });
@@ -319,7 +319,7 @@ describe("Rendezvous", function () {
        const alice = makeMockClient({
            userId: "alice",
            deviceId: "ALICE",
-            msc3882Enabled: true,
+            getLoginTokenEnabled: true,
            msc3882r0Only: false,
            msc3886Enabled: false,
        });
@@ -378,7 +378,7 @@ describe("Rendezvous", function () {
        const alice = makeMockClient({
            userId: "alice",
            deviceId: "ALICE",
-            msc3882Enabled: true,
+            getLoginTokenEnabled: true,
            msc3882r0Only: false,
            msc3886Enabled: false,
        });
@@ -439,7 +439,7 @@ describe("Rendezvous", function () {
        const alice = makeMockClient({
            userId: "alice",
            deviceId: "ALICE",
-            msc3882Enabled: true,
+            getLoginTokenEnabled: true,
            msc3882r0Only: false,
            msc3886Enabled: false,
        });
@@ -508,7 +508,7 @@ describe("Rendezvous", function () {
        const alice = makeMockClient({
            userId: "alice",
            deviceId: "ALICE",
-            msc3882Enabled: true,
+            getLoginTokenEnabled: true,
            msc3882r0Only: false,
            msc3886Enabled: false,
            devices,
@@ -27,6 +27,7 @@ import { M_BEACON } from "../../src/@types/beacon";
 import { MatrixClient } from "../../src/client";
 import { DecryptionError } from "../../src/crypto/algorithms";
 import { defer } from "../../src/utils";
+import { Room } from "../../src/models/room";

 describe("RoomState", function () {
    const roomId = "!foo:bar";
@@ -362,9 +363,11 @@ describe("RoomState", function () {
        });

        it("does not add redacted beacon info events to state", () => {
+            const mockClient = {} as unknown as MockedObject<MatrixClient>;
            const redactedBeaconEvent = makeBeaconInfoEvent(userA, roomId);
            const redactionEvent = new MatrixEvent({ type: "m.room.redaction" });
-            redactedBeaconEvent.makeRedacted(redactionEvent);
+            const room = new Room(roomId, mockClient, userA);
+            redactedBeaconEvent.makeRedacted(redactionEvent, room);
            const emitSpy = jest.spyOn(state, "emit");

            state.setStateEvents([redactedBeaconEvent]);
@@ -394,11 +397,13 @@ describe("RoomState", function () {
        });

        it("destroys and removes redacted beacon events", () => {
+            const mockClient = {} as unknown as MockedObject<MatrixClient>;
            const beaconId = "$beacon1";
            const beaconEvent = makeBeaconInfoEvent(userA, roomId, { isLive: true }, beaconId);
            const redactedBeaconEvent = makeBeaconInfoEvent(userA, roomId, { isLive: true }, beaconId);
            const redactionEvent = new MatrixEvent({ type: "m.room.redaction", redacts: beaconEvent.getId() });
-            redactedBeaconEvent.makeRedacted(redactionEvent);
+            const room = new Room(roomId, mockClient, userA);
+            redactedBeaconEvent.makeRedacted(redactionEvent, room);

            state.setStateEvents([beaconEvent]);
            const beaconInstance = state.beacons.get(getBeaconInfoIdentifier(beaconEvent));
@@ -1743,12 +1743,70 @@ describe("Room", function () {
        });

        describe("hasUserReadUpTo", function () {
-            it("should acknowledge if an event has been read", function () {
+            it("returns true if there is a receipt for this event (main timeline)", function () {
                const ts = 13787898424;
+                room.addLiveEvents([eventToAck]);
                room.addReceipt(mkReceipt(roomId, [mkRecord(eventToAck.getId()!, "m.read", userB, ts)]));
+                room.findEventById = jest.fn().mockReturnValue({ getThread: jest.fn() } as unknown as MatrixEvent);
                expect(room.hasUserReadEvent(userB, eventToAck.getId()!)).toEqual(true);
            });
-            it("return false for an unknown event", function () {
+
+            it("returns true if there is a receipt for a later event (main timeline)", async function () {
+                // Given some events exist in the room
+                const events: MatrixEvent[] = [
+                    utils.mkMessage({
+                        room: roomId,
+                        user: userA,
+                        msg: "1111",
+                        event: true,
+                    }),
+                    utils.mkMessage({
+                        room: roomId,
+                        user: userA,
+                        msg: "2222",
+                        event: true,
+                    }),
+                    utils.mkMessage({
+                        room: roomId,
+                        user: userA,
+                        msg: "3333",
+                        event: true,
+                    }),
+                ];
+                await room.addLiveEvents(events);
+
+                // When I add a receipt for the latest one
+                room.addReceipt(mkReceipt(roomId, [mkRecord(events[2].getId()!, "m.read", userB, 102)]));
+
+                // Then the older ones are read too
+                expect(room.hasUserReadEvent(userB, events[0].getId()!)).toEqual(true);
+                expect(room.hasUserReadEvent(userB, events[1].getId()!)).toEqual(true);
+            });
+
+            describe("threads enabled", () => {
+                beforeEach(() => {
+                    jest.spyOn(room.client, "supportsThreads").mockReturnValue(true);
+                });
+
+                afterEach(() => {
+                    jest.restoreAllMocks();
+                });
+
+                it("returns true if there is an unthreaded receipt for a later event in a thread", async () => {
+                    // Given a thread exists in the room
+                    const { thread, events } = mkThread({ room, length: 3 });
+                    thread.initialEventsFetched = true;
+                    await room.addLiveEvents(events);
+
+                    // When I add an unthreaded receipt for the latest thread message
+                    room.addReceipt(mkReceipt(roomId, [mkRecord(events[2].getId()!, "m.read", userB, 102)]));
+
+                    // Then the main timeline message is read
+                    expect(room.hasUserReadEvent(userB, events[0].getId()!)).toEqual(true);
+                });
+            });
+
+            it("returns false for an unknown event", function () {
                expect(room.hasUserReadEvent(userB, "unknown_event")).toEqual(false);
            });
        });
@@ -3147,106 +3205,194 @@ describe("Room", function () {
        const client = new TestClient(userA).client;
        const room = new Room(roomId, client, userA);

-        it("handles missing receipt type", () => {
-            room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
-                return receiptType === ReceiptType.ReadPrivate ? ({ eventId: "eventId" } as WrappedReceipt) : null;
-            };
-
-            expect(room.getEventReadUpTo(userA)).toEqual("eventId");
-        });
-
-        describe("prefers newer receipt", () => {
-            it("should compare correctly using timelines", () => {
-                room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
-                    if (receiptType === ReceiptType.ReadPrivate) {
-                        return { eventId: "eventId1" } as WrappedReceipt;
-                    }
-                    if (receiptType === ReceiptType.Read) {
-                        return { eventId: "eventId2" } as WrappedReceipt;
-                    }
-                    return null;
-                };
-
-                for (let i = 1; i <= 2; i++) {
-                    room.getUnfilteredTimelineSet = () =>
-                        ({
-                            compareEventOrdering: (event1, event2) => {
-                                return event1 === `eventId${i}` ? 1 : -1;
-                            },
-                        } as EventTimelineSet);
-
-                    expect(room.getEventReadUpTo(userA)).toEqual(`eventId${i}`);
-                }
+        describe("invalid receipts", () => {
+            beforeEach(() => {
+                // Clear the spies on logger.warn
+                jest.clearAllMocks();
            });

-            describe("correctly compares by timestamp", () => {
-                it("should correctly compare, if we have all receipts", () => {
+            it("ignores receipts pointing at missing events", () => {
+                // Given a receipt exists
+                room.getReadReceiptForUserId = (): WrappedReceipt | null => {
+                    return { eventId: "missingEventId" } as WrappedReceipt;
+                };
+                // But the event ID it contains does not refer to an event we have
+                room.findEventById = jest.fn().mockReturnValue(null);
+
+                // When we ask what they have read
+                // Then we say "nothing"
+                expect(room.getEventReadUpTo(userA)).toBeNull();
+            });
+
+            it("ignores receipts pointing at the wrong thread", () => {
+                // Given a threaded receipt exists
+                room.getReadReceiptForUserId = (): WrappedReceipt | null => {
+                    return { eventId: "wrongThreadEventId", data: { ts: 0, thread_id: "thread1" } } as WrappedReceipt;
+                };
+                // But the event it refers to is in a thread
+                room.findEventById = jest.fn().mockReturnValue({ threadRootId: "thread2" } as MatrixEvent);
+
+                // When we ask what they have read
+                // Then we say "nothing"
+                expect(room.getEventReadUpTo(userA)).toBeNull();
+                expect(logger.warn).toHaveBeenCalledWith(
+                    "Ignoring receipt because its thread_id (thread1) disagrees with the thread root (thread2) " +
+                        "of the referenced event (event ID = wrongThreadEventId)",
+                );
+            });
+
+            it("accepts unthreaded receipts pointing at an event in a thread", () => {
+                // Given an unthreaded receipt exists
+                room.getReadReceiptForUserId = (): WrappedReceipt | null => {
+                    return { eventId: "inThreadEventId" } as WrappedReceipt;
+                };
+                // And the event it refers to is in a thread
+                room.findEventById = jest.fn().mockReturnValue({ threadRootId: "thread2" } as MatrixEvent);
+
+                // When we ask what they have read
+                // Then we say the event
+                expect(room.getEventReadUpTo(userA)).toEqual("inThreadEventId");
+            });
+
+            it("accepts main thread receipts pointing at an event in main timeline", () => {
+                // Given a threaded receipt exists, in main thread
+                room.getReadReceiptForUserId = (): WrappedReceipt | null => {
+                    return { eventId: "mainThreadEventId", data: { ts: 12, thread_id: "main" } } as WrappedReceipt;
+                };
+                // And the event it refers to is in a thread
+                room.findEventById = jest.fn().mockReturnValue({ threadRootId: undefined } as MatrixEvent);
+
+                // When we ask what they have read
+                // Then we say the event
+                expect(room.getEventReadUpTo(userA)).toEqual("mainThreadEventId");
+            });
+
+            it("accepts main thread receipts pointing at a thread root", () => {
+                // Given a threaded receipt exists, in main thread
+                room.getReadReceiptForUserId = (): WrappedReceipt | null => {
+                    return { eventId: "rootId", data: { ts: 12, thread_id: "main" } } as WrappedReceipt;
+                };
+                // And the event it refers to is in a thread, because it is a thread root
+                room.findEventById = jest
+                    .fn()
+                    .mockReturnValue({ isThreadRoot: true, threadRootId: "thread1" } as MatrixEvent);
+
+                // When we ask what they have read
+                // Then we say the event
+                expect(room.getEventReadUpTo(userA)).toEqual("rootId");
+            });
+        });
+
+        describe("valid receipts", () => {
+            beforeEach(() => {
+                // When we look up the event referred to by the receipt, it exists
+                room.findEventById = jest.fn().mockReturnValue({} as MatrixEvent);
+            });
+
+            it("handles missing receipt type", () => {
+                room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
+                    return receiptType === ReceiptType.ReadPrivate ? ({ eventId: "eventId" } as WrappedReceipt) : null;
+                };
+                expect(room.getEventReadUpTo(userA)).toEqual("eventId");
+            });
+
+            describe("prefers newer receipt", () => {
+                it("should compare correctly using timelines", () => {
+                    room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
+                        if (receiptType === ReceiptType.ReadPrivate) {
+                            return { eventId: "eventId1" } as WrappedReceipt;
+                        }
+                        if (receiptType === ReceiptType.Read) {
+                            return { eventId: "eventId2" } as WrappedReceipt;
+                        }
+                        return null;
+                    };
+
                    for (let i = 1; i <= 2; i++) {
                        room.getUnfilteredTimelineSet = () =>
                            ({
-                                compareEventOrdering: (_1, _2) => null,
-                            } as EventTimelineSet);
-                        room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
-                            if (receiptType === ReceiptType.ReadPrivate) {
-                                return { eventId: "eventId1", data: { ts: i === 1 ? 2 : 1 } } as WrappedReceipt;
-                            }
-                            if (receiptType === ReceiptType.Read) {
-                                return { eventId: "eventId2", data: { ts: i === 2 ? 2 : 1 } } as WrappedReceipt;
-                            }
-                            return null;
-                        };
+                                compareEventOrdering: (event1: string, _event2: string) => {
+                                    return event1 === `eventId${i}` ? 1 : -1;
+                                },
+                                findEventById: jest.fn().mockReturnValue({} as MatrixEvent),
+                            }) as unknown as EventTimelineSet;

                        expect(room.getEventReadUpTo(userA)).toEqual(`eventId${i}`);
                    }
                });

-                it("should correctly compare, if private read receipt is missing", () => {
-                    room.getUnfilteredTimelineSet = () =>
-                        ({
-                            compareEventOrdering: (_1, _2) => null,
-                        } as EventTimelineSet);
-                    room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
-                        if (receiptType === ReceiptType.Read) {
-                            return { eventId: "eventId2", data: { ts: 1 } } as WrappedReceipt;
+                describe("correctly compares by timestamp", () => {
+                    it("should correctly compare, if we have all receipts", () => {
+                        for (let i = 1; i <= 2; i++) {
+                            room.getUnfilteredTimelineSet = () =>
+                                ({
+                                    compareEventOrdering: () => null,
+                                    findEventById: jest.fn().mockReturnValue({} as MatrixEvent),
+                                }) as unknown as EventTimelineSet;
+                            room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
+                                if (receiptType === ReceiptType.ReadPrivate) {
+                                    return { eventId: "eventId1", data: { ts: i === 1 ? 2 : 1 } } as WrappedReceipt;
+                                }
+                                if (receiptType === ReceiptType.Read) {
+                                    return { eventId: "eventId2", data: { ts: i === 2 ? 2 : 1 } } as WrappedReceipt;
+                                }
+                                return null;
+                            };
+
+                            expect(room.getEventReadUpTo(userA)).toEqual(`eventId${i}`);
                        }
-                        return null;
-                    };
+                    });

-                    expect(room.getEventReadUpTo(userA)).toEqual(`eventId2`);
-                });
-            });
+                    it("should correctly compare, if private read receipt is missing", () => {
+                        room.getUnfilteredTimelineSet = () =>
+                            ({
+                                compareEventOrdering: () => null,
+                                findEventById: jest.fn().mockReturnValue({} as MatrixEvent),
+                            }) as unknown as EventTimelineSet;
+                        room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
+                            if (receiptType === ReceiptType.Read) {
+                                return { eventId: "eventId2", data: { ts: 1 } } as WrappedReceipt;
+                            }
+                            return null;
+                        };

-            describe("fallback precedence", () => {
-                beforeAll(() => {
-                    room.getUnfilteredTimelineSet = () =>
-                        ({
-                            compareEventOrdering: (_1, _2) => null,
-                        } as EventTimelineSet);
+                        expect(room.getEventReadUpTo(userA)).toEqual(`eventId2`);
+                    });
                });

-                it("should give precedence to m.read.private", () => {
-                    room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
-                        if (receiptType === ReceiptType.ReadPrivate) {
-                            return { eventId: "eventId1", data: { ts: 123 } };
-                        }
-                        if (receiptType === ReceiptType.Read) {
-                            return { eventId: "eventId2", data: { ts: 123 } };
-                        }
-                        return null;
-                    };
+                describe("fallback precedence", () => {
+                    beforeAll(() => {
+                        room.getUnfilteredTimelineSet = () =>
+                            ({
+                                compareEventOrdering: () => null,
+                                findEventById: jest.fn().mockReturnValue({} as MatrixEvent),
+                            }) as unknown as EventTimelineSet;
+                    });

-                    expect(room.getEventReadUpTo(userA)).toEqual(`eventId1`);
-                });
+                    it("should give precedence to m.read.private", () => {
+                        room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
+                            if (receiptType === ReceiptType.ReadPrivate) {
+                                return { eventId: "eventId1", data: { ts: 123 } };
+                            }
+                            if (receiptType === ReceiptType.Read) {
+                                return { eventId: "eventId2", data: { ts: 123 } };
+                            }
+                            return null;
+                        };

-                it("should give precedence to m.read", () => {
-                    room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
-                        if (receiptType === ReceiptType.Read) {
-                            return { eventId: "eventId3" } as WrappedReceipt;
-                        }
-                        return null;
-                    };
+                        expect(room.getEventReadUpTo(userA)).toEqual(`eventId1`);
+                    });

-                    expect(room.getEventReadUpTo(userA)).toEqual(`eventId3`);
+                    it("should give precedence to m.read", () => {
+                        room.getReadReceiptForUserId = (userId, ignore, receiptType): WrappedReceipt | null => {
+                            if (receiptType === ReceiptType.Read) {
+                                return { eventId: "eventId3" } as WrappedReceipt;
+                            }
+                            return null;
+                        };
+
+                        expect(room.getEventReadUpTo(userA)).toEqual(`eventId3`);
+                    });
                });
            });
        });
@@ -3564,7 +3710,7 @@ describe("Room", function () {
            expect(room.polls.get(pollStartEvent.getId()!)).toBeTruthy();

            const redactedEvent = new MatrixEvent({ type: "m.room.redaction" });
-            pollStartEvent.makeRedacted(redactedEvent);
+            pollStartEvent.makeRedacted(redactedEvent, room);

            await flushPromises();

@@ -41,6 +41,7 @@ describe("CrossSigningIdentity", () => {
            olmMachine = {
                crossSigningStatus: jest.fn(),
                bootstrapCrossSigning: jest.fn(),
+                exportCrossSigningKeys: jest.fn(),
                close: jest.fn(),
            } as unknown as Mocked<RustSdkCryptoJs.OlmMachine>;

@@ -50,6 +51,8 @@ describe("CrossSigningIdentity", () => {

            secretStorage = {
                get: jest.fn(),
+                hasKey: jest.fn(),
+                store: jest.fn(),
            } as unknown as Mocked<ServerSideSecretStorage>;

            crossSigning = new CrossSigningIdentity(olmMachine, outgoingRequestProcessor, secretStorage);
@@ -61,7 +64,8 @@ describe("CrossSigningIdentity", () => {
                hasSelfSigning: true,
                hasUserSigning: true,
            });
-            // TODO: secret storage
+            // in secret storage
+            secretStorage.get.mockResolvedValue("base64-saved-in-storage");
            await crossSigning.bootstrapCrossSigning({});
            expect(olmMachine.bootstrapCrossSigning).not.toHaveBeenCalled();
            expect(outgoingRequestProcessor.makeOutgoingRequest).not.toHaveBeenCalled();
@@ -73,6 +77,19 @@ describe("CrossSigningIdentity", () => {
            expect(olmMachine.bootstrapCrossSigning).toHaveBeenCalledWith(true);
        });

+        it("Shoud update 4S on reset if 4S is set up", async () => {
+            olmMachine.bootstrapCrossSigning.mockResolvedValue([]);
+            secretStorage.hasKey.mockResolvedValue(true);
+            olmMachine.exportCrossSigningKeys.mockResolvedValue({
+                masterKey: "base64_aaaaaaaaaa",
+                self_signing_key: "base64_bbbbbbbbbbb",
+                userSigningKey: "base64_cccccccc",
+            });
+            await crossSigning.bootstrapCrossSigning({ setupNewCrossSigning: true });
+            expect(olmMachine.bootstrapCrossSigning).toHaveBeenCalledWith(true);
+            expect(secretStorage.store).toHaveBeenCalledTimes(3);
+        });
+
        it("should call bootstrapCrossSigning if we need new keys", async () => {
            olmMachine.crossSigningStatus.mockResolvedValue({
                hasMaster: false,
@@ -23,6 +23,7 @@ import { OutgoingRequestProcessor } from "../../../src/rust-crypto/OutgoingReque
 import { KeyClaimManager } from "../../../src/rust-crypto/KeyClaimManager";
 import { TypedEventEmitter } from "../../../src/models/typed-event-emitter";
 import { HttpApiEvent, HttpApiEventHandlerMap, MatrixHttpApi } from "../../../src";
+import { logger, LogSpan } from "../../../src/logger";

 afterEach(() => {
    fetchMock.mockReset();
@@ -93,7 +94,7 @@ describe("KeyClaimManager", () => {
        olmMachine.markRequestAsSent.mockResolvedValueOnce(undefined);

        // fire off the request
-        await keyClaimManager.ensureSessionsForUsers([u1, u2]);
+        await keyClaimManager.ensureSessionsForUsers(new LogSpan(logger, "test"), [u1, u2]);

        // check that all the calls were made
        expect(olmMachine.getMissingSessions).toHaveBeenCalledWith([u1, u2]);
@@ -119,12 +120,13 @@ describe("KeyClaimManager", () => {
        let markRequestAsSentPromise = awaitCallToMarkRequestAsSent();

        // fire off two requests, and keep track of whether their promises resolve
+        const span = new LogSpan(logger, "test");
        let req1Resolved = false;
-        keyClaimManager.ensureSessionsForUsers([u1]).then(() => {
+        keyClaimManager.ensureSessionsForUsers(span, [u1]).then(() => {
            req1Resolved = true;
        });
        let req2Resolved = false;
-        const req2 = keyClaimManager.ensureSessionsForUsers([u2]).then(() => {
+        const req2 = keyClaimManager.ensureSessionsForUsers(span, [u2]).then(() => {
            req2Resolved = true;
        });

@@ -24,7 +24,7 @@ import {
    KeysUploadRequest,
    RoomMessageRequest,
    SignatureUploadRequest,
-    SigningKeysUploadRequest,
+    UploadSigningKeysRequest,
    ToDeviceRequest,
 } from "@matrix-org/matrix-sdk-crypto-wasm";

@@ -82,12 +82,6 @@ describe("OutgoingRequestProcessor", () => {
            "https://example.com/_matrix/client/v3/keys/signatures/upload",
        ],
        ["KeysBackupRequest", KeysBackupRequest, "PUT", "https://example.com/_matrix/client/v3/room_keys/keys"],
-        [
-            "SigningKeysUploadRequest",
-            SigningKeysUploadRequest,
-            "POST",
-            "https://example.com/_matrix/client/v3/keys/device_signing/upload",
-        ],
    ];

    test.each(tests)(`should handle %ss`, async (_, RequestClass, expectedMethod, expectedPath) => {
@@ -121,7 +115,7 @@ describe("OutgoingRequestProcessor", () => {

    it("should handle ToDeviceRequests", async () => {
        // first, mock up the ToDeviceRequest as we might expect to receive it from the Rust layer ...
-        const testBody = '{ "foo": "bar" }';
+        const testBody = '{ "messages": { "user": {"device": "bar" }}}';
        const outgoingRequest = new ToDeviceRequest("1234", "test/type", "test/txnid", testBody);

        // ... then poke it into the OutgoingRequestProcessor under test.
@@ -179,10 +173,37 @@ describe("OutgoingRequestProcessor", () => {
        httpBackend.verifyNoOutstandingRequests();
    });

-    it("should handle SigningKeysUploadRequests with UIA", async () => {
+    it("should handle UploadSigningKeysRequest without UIA", async () => {
        // first, mock up a request as we might expect to receive it from the Rust layer ...
        const testReq = { foo: "bar" };
-        const outgoingRequest = new SigningKeysUploadRequest("1234", JSON.stringify(testReq));
+        const outgoingRequest = new UploadSigningKeysRequest(JSON.stringify(testReq));
+
+        // ... then poke the request into the OutgoingRequestProcessor under test
+        const reqProm = processor.makeOutgoingRequest(outgoingRequest);
+
+        // Now: check that it makes a matching HTTP request.
+        const testResponse = '{"result":1}';
+        httpBackend
+            .when("POST", "/_matrix")
+            .check((req) => {
+                expect(req.path).toEqual("https://example.com/_matrix/client/v3/keys/device_signing/upload");
+                expect(JSON.parse(req.rawData)).toEqual(testReq);
+                expect(req.headers["Accept"]).toEqual("application/json");
+                expect(req.headers["Content-Type"]).toEqual("application/json");
+            })
+            .respond(200, testResponse, true);
+
+        // SigningKeysUploadRequest does not need to be marked as sent, so no call to OlmMachine.markAsSent is expected.
+
+        await httpBackend.flushAllExpected();
+        await reqProm;
+        httpBackend.verifyNoOutstandingRequests();
+    });
+
+    it("should handle UploadSigningKeysRequest with UIA", async () => {
+        // first, mock up a request as we might expect to receive it from the Rust layer ...
+        const testReq = { foo: "bar" };
+        const outgoingRequest = new UploadSigningKeysRequest(JSON.stringify(testReq));

        // also create a UIA callback
        const authCallback: UIAuthCallback<Object> = async (makeRequest) => {
@@ -192,7 +213,7 @@ describe("OutgoingRequestProcessor", () => {
        // ... then poke the request into the OutgoingRequestProcessor under test
        const reqProm = processor.makeOutgoingRequest(outgoingRequest, authCallback);

-        // Now: check that it makes a matching HTTP request ...
+        // Now: check that it makes a matching HTTP request.
        const testResponse = '{"result":1}';
        httpBackend
            .when("POST", "/_matrix")
@@ -204,12 +225,10 @@ describe("OutgoingRequestProcessor", () => {
            })
            .respond(200, testResponse, true);

-        // ... and that it calls OlmMachine.markAsSent.
-        const markSentCallPromise = awaitCallToMarkAsSent();
-        await httpBackend.flushAllExpected();
+        // SigningKeysUploadRequest does not need to be marked as sent, so no call to OlmMachine.markAsSent is expected.

-        await Promise.all([reqProm, markSentCallPromise]);
-        expect(olmMachine.markRequestAsSent).toHaveBeenCalledWith("1234", outgoingRequest.type, testResponse);
+        await httpBackend.flushAllExpected();
+        await reqProm;
        httpBackend.verifyNoOutstandingRequests();
    });

@@ -0,0 +1,237 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { Mocked } from "jest-mock";
+import * as RustSdkCryptoJs from "@matrix-org/matrix-sdk-crypto-wasm";
+
+import { OutgoingRequest, OutgoingRequestProcessor } from "../../../src/rust-crypto/OutgoingRequestProcessor";
+import { OutgoingRequestsManager } from "../../../src/rust-crypto/OutgoingRequestsManager";
+import { defer, IDeferred } from "../../../src/utils";
+import { logger } from "../../../src/logger";
+
+describe("OutgoingRequestsManager", () => {
+    /** the OutgoingRequestsManager implementation under test */
+    let manager: OutgoingRequestsManager;
+
+    /** a mock OutgoingRequestProcessor */
+    let processor: Mocked<OutgoingRequestProcessor>;
+
+    /** a mocked-up OlmMachine which manager is connected to */
+    let olmMachine: Mocked<RustSdkCryptoJs.OlmMachine>;
+
+    beforeEach(async () => {
+        olmMachine = {
+            outgoingRequests: jest.fn(),
+        } as unknown as Mocked<RustSdkCryptoJs.OlmMachine>;
+
+        processor = {
+            makeOutgoingRequest: jest.fn(),
+        } as unknown as Mocked<OutgoingRequestProcessor>;
+
+        manager = new OutgoingRequestsManager(logger, olmMachine, processor);
+    });
+
+    describe("Call doProcessOutgoingRequests", () => {
+        it("The call triggers handling of the machine outgoing requests", async () => {
+            const request1 = new RustSdkCryptoJs.KeysQueryRequest("foo", "{}");
+            const request2 = new RustSdkCryptoJs.KeysUploadRequest("foo2", "{}");
+            olmMachine.outgoingRequests.mockImplementationOnce(async () => {
+                return [request1, request2];
+            });
+
+            processor.makeOutgoingRequest.mockImplementationOnce(async () => {
+                return;
+            });
+
+            await manager.doProcessOutgoingRequests();
+
+            expect(olmMachine.outgoingRequests).toHaveBeenCalledTimes(1);
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledTimes(2);
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledWith(request1);
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledWith(request2);
+        });
+
+        it("Stack and batch calls to doProcessOutgoingRequests while one is already running", async () => {
+            const request1 = new RustSdkCryptoJs.KeysQueryRequest("foo", "{}");
+            const request2 = new RustSdkCryptoJs.KeysUploadRequest("foo2", "{}");
+            const request3 = new RustSdkCryptoJs.KeysBackupRequest("foo3", "{}", "1");
+
+            const firstOutgoingRequestDefer = defer<OutgoingRequest[]>();
+
+            olmMachine.outgoingRequests
+                .mockImplementationOnce(async (): Promise<OutgoingRequest[]> => {
+                    return firstOutgoingRequestDefer.promise;
+                })
+                .mockImplementationOnce(async () => {
+                    return [request3];
+                });
+
+            const firstRequest = manager.doProcessOutgoingRequests();
+
+            // stack 2 additional requests while the first one is still running
+            const secondRequest = manager.doProcessOutgoingRequests();
+            const thirdRequest = manager.doProcessOutgoingRequests();
+
+            // let the first request complete
+            firstOutgoingRequestDefer.resolve([request1, request2]);
+
+            await firstRequest;
+            await secondRequest;
+            await thirdRequest;
+
+            // outgoingRequests should be called twice in total, as the second and third requests are
+            // processed in the same loop.
+            expect(olmMachine.outgoingRequests).toHaveBeenCalledTimes(2);
+
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledTimes(3);
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledWith(request1);
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledWith(request2);
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledWith(request3);
+        });
+
+        it("Process 3 consecutive calls to doProcessOutgoingRequests while not blocking previous ones", async () => {
+            const request1 = new RustSdkCryptoJs.KeysQueryRequest("foo", "{}");
+            const request2 = new RustSdkCryptoJs.KeysUploadRequest("foo2", "{}");
+            const request3 = new RustSdkCryptoJs.KeysBackupRequest("foo3", "{}", "1");
+
+            // promises which will resolve when OlmMachine.outgoingRequests is called
+            const outgoingRequestCalledPromises: Promise<void>[] = [];
+
+            // deferreds which will provide the results of OlmMachine.outgoingRequests
+            const outgoingRequestResultDeferreds: IDeferred<OutgoingRequest[]>[] = [];
+
+            for (let i = 0; i < 3; i++) {
+                const resultDeferred = defer<OutgoingRequest[]>();
+                const calledPromise = new Promise<void>((resolve) => {
+                    olmMachine.outgoingRequests.mockImplementationOnce(() => {
+                        resolve();
+                        return resultDeferred.promise;
+                    });
+                });
+                outgoingRequestCalledPromises.push(calledPromise);
+                outgoingRequestResultDeferreds.push(resultDeferred);
+            }
+
+            const call1 = manager.doProcessOutgoingRequests();
+
+            // First call will start an iteration and for now is awaiting on outgoingRequests
+            expect(olmMachine.outgoingRequests).toHaveBeenCalledTimes(1);
+
+            // Make a new call now: this will request a new iteration
+            const call2 = manager.doProcessOutgoingRequests();
+
+            // let the first iteration complete
+            outgoingRequestResultDeferreds[0].resolve([request1]);
+
+            // The first call should now complete
+            await call1;
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledTimes(1);
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledWith(request1);
+
+            // Wait for the second iteration to fire and be waiting on `outgoingRequests`
+            await outgoingRequestCalledPromises[1];
+            expect(olmMachine.outgoingRequests).toHaveBeenCalledTimes(2);
+
+            // Stack a new call that should be processed in an additional iteration.
+            const call3 = manager.doProcessOutgoingRequests();
+
+            outgoingRequestResultDeferreds[1].resolve([request2]);
+            await call2;
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledTimes(2);
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledWith(request2);
+
+            // Wait for the third iteration to fire and be waiting on `outgoingRequests`
+            await outgoingRequestCalledPromises[2];
+            expect(olmMachine.outgoingRequests).toHaveBeenCalledTimes(3);
+            outgoingRequestResultDeferreds[2].resolve([request3]);
+            await call3;
+
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledTimes(3);
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledWith(request3);
+
+            // ensure that no other iteration is going on
+            expect(olmMachine.outgoingRequests).toHaveBeenCalledTimes(3);
+        });
+
+        it("Should not bubble exceptions if server request is rejected", async () => {
+            const request = new RustSdkCryptoJs.KeysQueryRequest("foo", "{}");
+            olmMachine.outgoingRequests.mockImplementationOnce(async () => {
+                return [request];
+            });
+
+            processor.makeOutgoingRequest.mockImplementationOnce(async () => {
+                throw new Error("Some network error");
+            });
+
+            await manager.doProcessOutgoingRequests();
+
+            expect(olmMachine.outgoingRequests).toHaveBeenCalledTimes(1);
+        });
+    });
+
+    describe("Calling stop on the manager should stop ongoing work", () => {
+        it("When the manager is stopped after outgoingRequests() call, do not make sever requests", async () => {
+            const request1 = new RustSdkCryptoJs.KeysQueryRequest("foo", "{}");
+
+            const firstOutgoingRequestDefer = defer<OutgoingRequest[]>();
+
+            olmMachine.outgoingRequests.mockImplementationOnce(async (): Promise<OutgoingRequest[]> => {
+                return firstOutgoingRequestDefer.promise;
+            });
+
+            const firstRequest = manager.doProcessOutgoingRequests();
+
+            // stop
+            manager.stop();
+
+            // let the first request complete
+            firstOutgoingRequestDefer.resolve([request1]);
+
+            await firstRequest;
+
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledTimes(0);
+        });
+
+        it("When the manager is stopped while doing server calls, it should stop before the next sever call", async () => {
+            const request1 = new RustSdkCryptoJs.KeysQueryRequest("11", "{}");
+            const request2 = new RustSdkCryptoJs.KeysUploadRequest("12", "{}");
+
+            const firstRequestDefer = defer<void>();
+
+            olmMachine.outgoingRequests.mockImplementationOnce(async (): Promise<OutgoingRequest[]> => {
+                return [request1, request2];
+            });
+
+            processor.makeOutgoingRequest
+                .mockImplementationOnce(async () => {
+                    manager.stop();
+                    return firstRequestDefer.promise;
+                })
+                .mockImplementationOnce(async () => {
+                    return;
+                });
+
+            const firstRequest = manager.doProcessOutgoingRequests();
+
+            firstRequestDefer.resolve();
+
+            await firstRequest;
+
+            // should have been called once but not twice
+            expect(processor.makeOutgoingRequest).toHaveBeenCalledTimes(1);
+        });
+    });
+});
@@ -0,0 +1,598 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+import { Mocked, SpyInstance } from "jest-mock";
+import * as RustSdkCryptoJs from "@matrix-org/matrix-sdk-crypto-wasm";
+import { OlmMachine } from "@matrix-org/matrix-sdk-crypto-wasm";
+import fetchMock from "fetch-mock-jest";
+
+import { PerSessionKeyBackupDownloader } from "../../../src/rust-crypto/PerSessionKeyBackupDownloader";
+import { logger } from "../../../src/logger";
+import { defer, IDeferred } from "../../../src/utils";
+import { RustBackupCryptoEventMap, RustBackupCryptoEvents, RustBackupManager } from "../../../src/rust-crypto/backup";
+import * as TestData from "../../test-utils/test-data";
+import {
+    ConnectionError,
+    CryptoEvent,
+    HttpApiEvent,
+    HttpApiEventHandlerMap,
+    IHttpOpts,
+    IMegolmSessionData,
+    MatrixHttpApi,
+    TypedEventEmitter,
+} from "../../../src";
+import * as testData from "../../test-utils/test-data";
+import { BackupDecryptor } from "../../../src/common-crypto/CryptoBackend";
+import { KeyBackupSession } from "../../../src/crypto-api/keybackup";
+
+describe("PerSessionKeyBackupDownloader", () => {
+    /** The downloader under test */
+    let downloader: PerSessionKeyBackupDownloader;
+
+    const mockCipherKey: Mocked<KeyBackupSession> = {} as unknown as Mocked<KeyBackupSession>;
+
+    // matches the const in PerSessionKeyBackupDownloader
+    const BACKOFF_TIME = 5000;
+
+    let mockEmitter: TypedEventEmitter<RustBackupCryptoEvents, RustBackupCryptoEventMap>;
+    let mockHttp: MatrixHttpApi<IHttpOpts & { onlyData: true }>;
+    let mockRustBackupManager: Mocked<RustBackupManager>;
+    let mockOlmMachine: Mocked<OlmMachine>;
+    let mockBackupDecryptor: Mocked<BackupDecryptor>;
+
+    let expectedSession: { [roomId: string]: { [sessionId: string]: IDeferred<void> } };
+
+    function expectSessionImported(roomId: string, sessionId: string) {
+        const deferred = defer<void>();
+        if (!expectedSession[roomId]) {
+            expectedSession[roomId] = {};
+        }
+        expectedSession[roomId][sessionId] = deferred;
+        return deferred.promise;
+    }
+
+    function mockClearSession(sessionId: string): Mocked<IMegolmSessionData> {
+        return {
+            session_id: sessionId,
+        } as unknown as Mocked<IMegolmSessionData>;
+    }
+
+    beforeEach(async () => {
+        mockEmitter = new TypedEventEmitter() as TypedEventEmitter<RustBackupCryptoEvents, RustBackupCryptoEventMap>;
+
+        mockHttp = new MatrixHttpApi(new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>(), {
+            baseUrl: "http://server/",
+            prefix: "",
+            onlyData: true,
+        });
+
+        mockBackupDecryptor = {
+            decryptSessions: jest.fn(),
+        } as unknown as Mocked<BackupDecryptor>;
+
+        mockBackupDecryptor.decryptSessions.mockImplementation(async (ciphertexts) => {
+            const sessionId = Object.keys(ciphertexts)[0];
+            return [mockClearSession(sessionId)];
+        });
+
+        mockRustBackupManager = {
+            getActiveBackupVersion: jest.fn(),
+            requestKeyBackupVersion: jest.fn(),
+            importBackedUpRoomKeys: jest.fn(),
+            createBackupDecryptor: jest.fn().mockReturnValue(mockBackupDecryptor),
+            on: jest.fn().mockImplementation((event, listener) => {
+                mockEmitter.on(event, listener);
+            }),
+            off: jest.fn().mockImplementation((event, listener) => {
+                mockEmitter.off(event, listener);
+            }),
+        } as unknown as Mocked<RustBackupManager>;
+
+        mockOlmMachine = {
+            getBackupKeys: jest.fn(),
+        } as unknown as Mocked<OlmMachine>;
+
+        downloader = new PerSessionKeyBackupDownloader(logger, mockOlmMachine, mockHttp, mockRustBackupManager);
+
+        expectedSession = {};
+        mockRustBackupManager.importBackedUpRoomKeys.mockImplementation(async (keys) => {
+            const roomId = keys[0].room_id;
+            const sessionId = keys[0].session_id;
+            const deferred = expectedSession[roomId] && expectedSession[roomId][sessionId];
+            if (deferred) {
+                deferred.resolve();
+            }
+        });
+
+        jest.useFakeTimers();
+    });
+
+    afterEach(() => {
+        expectedSession = {};
+        downloader.stop();
+        fetchMock.mockReset();
+        jest.useRealTimers();
+    });
+
+    describe("Given valid backup available", () => {
+        beforeEach(async () => {
+            mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA.version!);
+            mockOlmMachine.getBackupKeys.mockResolvedValue({
+                backupVersion: TestData.SIGNED_BACKUP_DATA.version!,
+                decryptionKey: RustSdkCryptoJs.BackupDecryptionKey.fromBase64(TestData.BACKUP_DECRYPTION_KEY_BASE64),
+            } as unknown as RustSdkCryptoJs.BackupKeys);
+
+            mockRustBackupManager.requestKeyBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA);
+        });
+
+        it("Should download and import a missing key from backup", async () => {
+            const awaitKeyImported = defer<void>();
+            const roomId = "!roomId";
+            const sessionId = "sessionId";
+            const expectAPICall = new Promise<void>((resolve) => {
+                fetchMock.get(`path:/_matrix/client/v3/room_keys/keys/${roomId}/${sessionId}`, (url, request) => {
+                    resolve();
+                    return TestData.CURVE25519_KEY_BACKUP_DATA;
+                });
+            });
+            mockRustBackupManager.importBackedUpRoomKeys.mockImplementation(async (keys) => {
+                awaitKeyImported.resolve();
+            });
+            mockBackupDecryptor.decryptSessions.mockResolvedValue([TestData.MEGOLM_SESSION_DATA]);
+
+            downloader.onDecryptionKeyMissingError(roomId, sessionId);
+
+            await expectAPICall;
+            await awaitKeyImported.promise;
+            expect(mockRustBackupManager.createBackupDecryptor).toHaveBeenCalledTimes(1);
+        });
+
+        it("Should not hammer the backup if the key is requested repeatedly", async () => {
+            const blockOnServerRequest = defer<void>();
+
+            fetchMock.get(`express:/_matrix/client/v3/room_keys/keys/!roomId/:session_id`, async (url, request) => {
+                await blockOnServerRequest.promise;
+                return [mockCipherKey];
+            });
+
+            const awaitKey2Imported = defer<void>();
+
+            mockRustBackupManager.importBackedUpRoomKeys.mockImplementation(async (keys) => {
+                if (keys[0].session_id === "sessionId2") {
+                    awaitKey2Imported.resolve();
+                }
+            });
+
+            // @ts-ignore access to private function
+            const spy = jest.spyOn(downloader, "queryKeyBackup");
+
+            // Call 3 times for same key
+            downloader.onDecryptionKeyMissingError("!roomId", "sessionId");
+            downloader.onDecryptionKeyMissingError("!roomId", "sessionId");
+            downloader.onDecryptionKeyMissingError("!roomId", "sessionId");
+
+            // Call again for a different key
+            downloader.onDecryptionKeyMissingError("!roomId", "sessionId2");
+
+            // Allow the first server request to complete
+            blockOnServerRequest.resolve();
+
+            await awaitKey2Imported.promise;
+            expect(spy).toHaveBeenCalledTimes(2);
+        });
+
+        it("should continue to next key if current not in backup", async () => {
+            fetchMock.get(`path:/_matrix/client/v3/room_keys/keys/!roomA/sessionA0`, {
+                status: 404,
+                body: {
+                    errcode: "M_NOT_FOUND",
+                    error: "No backup found",
+                },
+            });
+            fetchMock.get(`path:/_matrix/client/v3/room_keys/keys/!roomA/sessionA1`, mockCipherKey);
+
+            // @ts-ignore access to private function
+            const spy: SpyInstance = jest.spyOn(downloader, "queryKeyBackup");
+
+            const expectImported = expectSessionImported("!roomA", "sessionA1");
+
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA0");
+            await jest.runAllTimersAsync();
+            expect(spy).toHaveBeenCalledTimes(1);
+            expect(spy).toHaveLastReturnedWith(Promise.resolve({ ok: false, error: "MISSING_DECRYPTION_KEY" }));
+
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA1");
+            await jest.runAllTimersAsync();
+            expect(spy).toHaveBeenCalledTimes(2);
+
+            await expectImported;
+        });
+
+        it("Should not query repeatedly for a key not in backup", async () => {
+            fetchMock.get(`path:/_matrix/client/v3/room_keys/keys/!roomA/sessionA0`, {
+                status: 404,
+                body: {
+                    errcode: "M_NOT_FOUND",
+                    error: "No backup found",
+                },
+            });
+
+            // @ts-ignore access to private function
+            const spy: SpyInstance = jest.spyOn(downloader, "queryKeyBackup");
+
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA0");
+            await jest.runAllTimersAsync();
+
+            expect(spy).toHaveBeenCalledTimes(1);
+            const returnedPromise = spy.mock.results[0].value;
+            await expect(returnedPromise).rejects.toThrow("Failed to get key from backup: MISSING_DECRYPTION_KEY");
+
+            // Should not query again for a key not in backup
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA0");
+            await jest.runAllTimersAsync();
+
+            expect(spy).toHaveBeenCalledTimes(1);
+
+            // advance time to retry
+            jest.advanceTimersByTime(BACKOFF_TIME + 10);
+
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA0");
+            await jest.runAllTimersAsync();
+
+            expect(spy).toHaveBeenCalledTimes(2);
+            await expect(spy.mock.results[1].value).rejects.toThrow(
+                "Failed to get key from backup: MISSING_DECRYPTION_KEY",
+            );
+        });
+
+        it("Should stop properly", async () => {
+            // Simulate a call to stop while request is in flight
+            const blockOnServerRequest = defer<void>();
+            const requestRoomKeyCalled = defer<void>();
+
+            // Mock the request to block
+            fetchMock.get(`express:/_matrix/client/v3/room_keys/keys/:roomId/:sessionId`, async (url, request) => {
+                requestRoomKeyCalled.resolve();
+                await blockOnServerRequest.promise;
+                return mockCipherKey;
+            });
+
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA0");
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA1");
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA2");
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA3");
+
+            await requestRoomKeyCalled.promise;
+            downloader.stop();
+
+            blockOnServerRequest.resolve();
+
+            // let the first request complete
+            await jest.runAllTimersAsync();
+
+            expect(mockRustBackupManager.importBackedUpRoomKeys).not.toHaveBeenCalled();
+            expect(
+                fetchMock.calls(`express:/_matrix/client/v3/room_keys/keys/:roomId/:sessionId`).length,
+            ).toStrictEqual(1);
+        });
+    });
+
+    describe("Given no usable backup available", () => {
+        let getConfigSpy: SpyInstance;
+
+        beforeEach(async () => {
+            mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(null);
+            mockOlmMachine.getBackupKeys.mockResolvedValue(null);
+
+            // @ts-ignore access to private function
+            getConfigSpy = jest.spyOn(downloader, "getOrCreateBackupConfiguration");
+        });
+
+        it("Should not query server if no backup", async () => {
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", {
+                status: 404,
+                body: { errcode: "M_NOT_FOUND", error: "No current backup version." },
+            });
+
+            downloader.onDecryptionKeyMissingError("!roomId", "sessionId");
+
+            await jest.runAllTimersAsync();
+
+            expect(getConfigSpy).toHaveBeenCalledTimes(1);
+            expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+        });
+
+        it("Should not query server if backup not active", async () => {
+            // there is a backup
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);
+
+            // but it's not trusted
+            mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(null);
+
+            downloader.onDecryptionKeyMissingError("!roomId", "sessionId");
+
+            await jest.runAllTimersAsync();
+
+            expect(getConfigSpy).toHaveBeenCalledTimes(1);
+            expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+        });
+
+        it("Should stop if backup key is not cached", async () => {
+            // there is a backup
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);
+            // it is trusted
+            mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA.version!);
+            // but the key is not cached
+            mockOlmMachine.getBackupKeys.mockResolvedValue(null);
+
+            downloader.onDecryptionKeyMissingError("!roomId", "sessionId");
+
+            await jest.runAllTimersAsync();
+
+            expect(getConfigSpy).toHaveBeenCalledTimes(1);
+            expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+        });
+
+        it("Should stop if backup key cached as wrong version", async () => {
+            // there is a backup
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);
+            // it is trusted
+            mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA.version!);
+            // but the cached key has the wrong version
+            mockOlmMachine.getBackupKeys.mockResolvedValue({
+                backupVersion: "0",
+                decryptionKey: RustSdkCryptoJs.BackupDecryptionKey.fromBase64(TestData.BACKUP_DECRYPTION_KEY_BASE64),
+            } as unknown as RustSdkCryptoJs.BackupKeys);
+
+            downloader.onDecryptionKeyMissingError("!roomId", "sessionId");
+
+            await jest.runAllTimersAsync();
+
+            expect(getConfigSpy).toHaveBeenCalledTimes(1);
+            expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+        });
+
+        it("Should stop if backup key version does not match the active one", async () => {
+            // there is a backup
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);
+            // The sdk is out of sync, the trusted version is the old one
+            mockRustBackupManager.getActiveBackupVersion.mockResolvedValue("0");
+            // key for old backup cached
+            mockOlmMachine.getBackupKeys.mockResolvedValue({
+                backupVersion: "0",
+                decryptionKey: RustSdkCryptoJs.BackupDecryptionKey.fromBase64(TestData.BACKUP_DECRYPTION_KEY_BASE64),
+            } as unknown as RustSdkCryptoJs.BackupKeys);
+
+            downloader.onDecryptionKeyMissingError("!roomId", "sessionId");
+
+            await jest.runAllTimersAsync();
+
+            expect(getConfigSpy).toHaveBeenCalledTimes(1);
+            expect(getConfigSpy).toHaveReturnedWith(Promise.resolve(null));
+        });
+    });
+
+    describe("Given Backup state update", () => {
+        it("After initial sync, when backup becomes trusted it should request keys for past requests", async () => {
+            // there is a backup
+            mockRustBackupManager.requestKeyBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA);
+
+            // but at this point it's not trusted and we don't have the key
+            mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(null);
+            mockOlmMachine.getBackupKeys.mockResolvedValue(null);
+
+            fetchMock.get(`express:/_matrix/client/v3/room_keys/keys/:roomId/:sessionId`, mockCipherKey);
+
+            const a0Imported = expectSessionImported("!roomA", "sessionA0");
+            const a1Imported = expectSessionImported("!roomA", "sessionA1");
+            const b1Imported = expectSessionImported("!roomB", "sessionB1");
+            const c1Imported = expectSessionImported("!roomC", "sessionC1");
+
+            // During initial sync several keys are requested
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA0");
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA1");
+            downloader.onDecryptionKeyMissingError("!roomB", "sessionB1");
+            downloader.onDecryptionKeyMissingError("!roomC", "sessionC1");
+            await jest.runAllTimersAsync();
+
+            // @ts-ignore access to private property
+            expect(downloader.hasConfigurationProblem).toEqual(true);
+
+            // Now the backup becomes trusted
+            mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA.version!);
+            // And we have the key in cache
+            mockOlmMachine.getBackupKeys.mockResolvedValue({
+                backupVersion: TestData.SIGNED_BACKUP_DATA.version!,
+                decryptionKey: RustSdkCryptoJs.BackupDecryptionKey.fromBase64(TestData.BACKUP_DECRYPTION_KEY_BASE64),
+            } as unknown as RustSdkCryptoJs.BackupKeys);
+
+            // In that case the sdk would fire a backup status update
+            mockEmitter.emit(CryptoEvent.KeyBackupStatus, true);
+
+            await jest.runAllTimersAsync();
+
+            await a0Imported;
+            await a1Imported;
+            await b1Imported;
+            await c1Imported;
+        });
+    });
+
+    describe("Error cases", () => {
+        beforeEach(async () => {
+            // there is a backup
+            mockRustBackupManager.requestKeyBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA);
+            // It's trusted
+            mockRustBackupManager.getActiveBackupVersion.mockResolvedValue(TestData.SIGNED_BACKUP_DATA.version!);
+            // And we have the key in cache
+            mockOlmMachine.getBackupKeys.mockResolvedValue({
+                backupVersion: TestData.SIGNED_BACKUP_DATA.version!,
+                decryptionKey: RustSdkCryptoJs.BackupDecryptionKey.fromBase64(TestData.BACKUP_DECRYPTION_KEY_BASE64),
+            } as unknown as RustSdkCryptoJs.BackupKeys);
+        });
+
+        it("Should wait on rate limit error", async () => {
+            // simulate rate limit error
+            fetchMock.get(
+                `express:/_matrix/client/v3/room_keys/keys/:roomId/:sessionId`,
+                {
+                    status: 429,
+                    body: {
+                        errcode: "M_LIMIT_EXCEEDED",
+                        error: "Too many requests",
+                        retry_after_ms: 5000,
+                    },
+                },
+                { overwriteRoutes: true },
+            );
+
+            const keyImported = expectSessionImported("!roomA", "sessionA0");
+
+            // @ts-ignore
+            const originalImplementation = downloader.queryKeyBackup.bind(downloader);
+
+            // @ts-ignore access to private function
+            const keyQuerySpy: SpyInstance = jest.spyOn(downloader, "queryKeyBackup");
+            const rateDeferred = defer<void>();
+
+            keyQuerySpy.mockImplementation(
+                // @ts-ignore
+                async (targetRoomId: string, targetSessionId: string, configuration: any) => {
+                    try {
+                        return await originalImplementation(targetRoomId, targetSessionId, configuration);
+                    } catch (err: any) {
+                        if (err.name === "KeyDownloadRateLimitError") {
+                            rateDeferred.resolve();
+                        }
+                        throw err;
+                    }
+                },
+            );
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA0");
+
+            await rateDeferred.promise;
+            expect(keyQuerySpy).toHaveBeenCalledTimes(1);
+            await expect(keyQuerySpy.mock.results[0].value).rejects.toThrow(
+                "Failed to get key from backup: rate limited",
+            );
+
+            fetchMock.get(`express:/_matrix/client/v3/room_keys/keys/:roomId/:sessionId`, mockCipherKey, {
+                overwriteRoutes: true,
+            });
+
+            // Advance less than the retry_after_ms
+            jest.advanceTimersByTime(100);
+            // let any pending callbacks in PromiseJobs run
+            await Promise.resolve();
+            // no additional call should have been made
+            expect(keyQuerySpy).toHaveBeenCalledTimes(1);
+
+            // The loop should resume after the retry_after_ms
+            jest.advanceTimersByTime(5000);
+            // let any pending callbacks in PromiseJobs run
+            await Promise.resolve();
+
+            await keyImported;
+            expect(keyQuerySpy).toHaveBeenCalledTimes(2);
+        });
+
+        it("After a network error the same key is retried", async () => {
+            // simulate connectivity error
+            fetchMock.get(`express:/_matrix/client/v3/room_keys/keys/:roomId/:sessionId`, () => {
+                throw new ConnectionError("fetch failed", new Error("fetch failed"));
+            });
+
+            // @ts-ignore
+            const originalImplementation = downloader.queryKeyBackup.bind(downloader);
+
+            // @ts-ignore
+            const keyQuerySpy: SpyInstance = jest.spyOn(downloader, "queryKeyBackup");
+            const errorDeferred = defer<void>();
+
+            keyQuerySpy.mockImplementation(
+                // @ts-ignore
+                async (targetRoomId: string, targetSessionId: string, configuration: any) => {
+                    try {
+                        return await originalImplementation(targetRoomId, targetSessionId, configuration);
+                    } catch (err: any) {
+                        if (err.name === "KeyDownloadError") {
+                            errorDeferred.resolve();
+                        }
+                        throw err;
+                    }
+                },
+            );
+            const keyImported = expectSessionImported("!roomA", "sessionA0");
+
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA0");
+            await errorDeferred.promise;
+            await Promise.resolve();
+
+            await expect(keyQuerySpy.mock.results[0].value).rejects.toThrow(
+                "Failed to get key from backup: NETWORK_ERROR",
+            );
+
+            fetchMock.get(`express:/_matrix/client/v3/room_keys/keys/:roomId/:sessionId`, mockCipherKey, {
+                overwriteRoutes: true,
+            });
+
+            // Advance less than the retry_after_ms
+            jest.advanceTimersByTime(100);
+            // let any pending callbacks in PromiseJobs run
+            await Promise.resolve();
+            // no additional call should have been made
+            expect(keyQuerySpy).toHaveBeenCalledTimes(1);
+
+            // The loop should resume after the retry_after_ms
+            jest.advanceTimersByTime(BACKOFF_TIME + 100);
+            await Promise.resolve();
+
+            await keyImported;
+        });
+
+        it("On Unknown error on import skip the key and continue", async () => {
+            const keyImported = defer<void>();
+            mockRustBackupManager.importBackedUpRoomKeys
+                .mockImplementationOnce(async () => {
+                    throw new Error("Didn't work");
+                })
+                .mockImplementationOnce(async (sessions) => {
+                    const roomId = sessions[0].room_id;
+                    const sessionId = sessions[0].session_id;
+                    if (roomId === "!roomA" && sessionId === "sessionA1") {
+                        keyImported.resolve();
+                    }
+                    return;
+                });
+
+            fetchMock.get(`express:/_matrix/client/v3/room_keys/keys/:roomId/:sessionId`, mockCipherKey, {
+                overwriteRoutes: true,
+            });
+
+            // @ts-ignore access to private function
+            const keyQuerySpy: SpyInstance = jest.spyOn(downloader, "queryKeyBackup");
+
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA0");
+            downloader.onDecryptionKeyMissingError("!roomA", "sessionA1");
+            await jest.runAllTimersAsync();
+
+            await keyImported.promise;
+
+            expect(keyQuerySpy).toHaveBeenCalledTimes(2);
+            expect(mockRustBackupManager.importBackedUpRoomKeys).toHaveBeenCalledTimes(2);
+        });
+    });
+});
@@ -0,0 +1,184 @@
+/*
+ *
+ * Copyright 2023 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * /
+ */
+
+import {
+    Curve25519PublicKey,
+    Ed25519PublicKey,
+    HistoryVisibility as RustHistoryVisibility,
+    IdentityKeys,
+    OlmMachine,
+} from "@matrix-org/matrix-sdk-crypto-wasm";
+import { Mocked } from "jest-mock";
+
+import { HistoryVisibility, MatrixEvent, Room, RoomMember } from "../../../src";
+import { RoomEncryptor, toRustHistoryVisibility } from "../../../src/rust-crypto/RoomEncryptor";
+import { KeyClaimManager } from "../../../src/rust-crypto/KeyClaimManager";
+import { defer } from "../../../src/utils";
+import { OutgoingRequestsManager } from "../../../src/rust-crypto/OutgoingRequestsManager";
+
+describe("RoomEncryptor", () => {
+    describe("History Visibility", () => {
+        it.each([
+            [HistoryVisibility.Invited, RustHistoryVisibility.Invited],
+            [HistoryVisibility.Joined, RustHistoryVisibility.Joined],
+            [HistoryVisibility.Shared, RustHistoryVisibility.Shared],
+            [HistoryVisibility.WorldReadable, RustHistoryVisibility.WorldReadable],
+        ])("JS HistoryVisibility to Rust HistoryVisibility: converts %s to %s", (historyVisibility, expected) => {
+            expect(toRustHistoryVisibility(historyVisibility)).toBe(expected);
+        });
+    });
+
+    describe("RoomEncryptor", () => {
+        /** The room encryptor under test */
+        let roomEncryptor: RoomEncryptor;
+
+        let mockOlmMachine: Mocked<OlmMachine>;
+        let mockKeyClaimManager: Mocked<KeyClaimManager>;
+        let mockOutgoingRequestManager: Mocked<OutgoingRequestsManager>;
+        let mockRoom: Mocked<Room>;
+
+        const mockRoomMember = {
+            userId: "@alice:example.org",
+            membership: "join",
+        } as unknown as Mocked<RoomMember>;
+
+        function createMockEvent(text: string): Mocked<MatrixEvent> {
+            return {
+                getTxnId: jest.fn().mockReturnValue(""),
+                getType: jest.fn().mockReturnValue("m.room.message"),
+                getContent: jest.fn().mockReturnValue({
+                    body: text,
+                    msgtype: "m.text",
+                }),
+                makeEncrypted: jest.fn().mockReturnValue(undefined),
+            } as unknown as Mocked<MatrixEvent>;
+        }
+
+        beforeEach(() => {
+            mockOlmMachine = {
+                identityKeys: {
+                    curve25519: {
+                        toBase64: jest.fn().mockReturnValue("curve25519"),
+                    } as unknown as Curve25519PublicKey,
+                    ed25519: {
+                        toBase64: jest.fn().mockReturnValue("ed25519"),
+                    } as unknown as Ed25519PublicKey,
+                } as unknown as Mocked<IdentityKeys>,
+                shareRoomKey: jest.fn(),
+                updateTrackedUsers: jest.fn().mockResolvedValue(undefined),
+                encryptRoomEvent: jest.fn().mockResolvedValue("{}"),
+            } as unknown as Mocked<OlmMachine>;
+
+            mockKeyClaimManager = {
+                ensureSessionsForUsers: jest.fn(),
+            } as unknown as Mocked<KeyClaimManager>;
+
+            mockOutgoingRequestManager = {
+                doProcessOutgoingRequests: jest.fn().mockResolvedValue(undefined),
+            } as unknown as Mocked<OutgoingRequestsManager>;
+
+            mockRoom = {
+                roomId: "!foo:example.org",
+                getJoinedMembers: jest.fn().mockReturnValue([mockRoomMember]),
+                getEncryptionTargetMembers: jest.fn().mockReturnValue([mockRoomMember]),
+                shouldEncryptForInvitedMembers: jest.fn().mockReturnValue(true),
+                getHistoryVisibility: jest.fn().mockReturnValue(HistoryVisibility.Invited),
+                getBlacklistUnverifiedDevices: jest.fn().mockReturnValue(false),
+            } as unknown as Mocked<Room>;
+
+            roomEncryptor = new RoomEncryptor(
+                mockOlmMachine,
+                mockKeyClaimManager,
+                mockOutgoingRequestManager,
+                mockRoom,
+                { algorithm: "m.megolm.v1.aes-sha2" },
+            );
+        });
+
+        it("should ensure that there is only one shareRoomKey at a time", async () => {
+            const deferredShare = defer<void>();
+            const insideOlmShareRoom = defer<void>();
+
+            mockOlmMachine.shareRoomKey.mockImplementationOnce(async () => {
+                insideOlmShareRoom.resolve();
+                await deferredShare.promise;
+            });
+
+            roomEncryptor.prepareForEncryption(false);
+            await insideOlmShareRoom.promise;
+
+            // call several times more
+            roomEncryptor.prepareForEncryption(false);
+            roomEncryptor.encryptEvent(createMockEvent("Hello"), false);
+            roomEncryptor.prepareForEncryption(false);
+            roomEncryptor.encryptEvent(createMockEvent("World"), false);
+
+            expect(mockOlmMachine.shareRoomKey).toHaveBeenCalledTimes(1);
+
+            deferredShare.resolve();
+            await roomEncryptor.prepareForEncryption(false);
+
+            // should have been called again
+            expect(mockOlmMachine.shareRoomKey).toHaveBeenCalledTimes(6);
+        });
+
+        // Regression test for https://github.com/element-hq/element-web/issues/26684
+        it("Should maintain order of encryption requests", async () => {
+            const firstTargetMembers = defer<void>();
+            const secondTargetMembers = defer<void>();
+
+            mockOlmMachine.shareRoomKey.mockResolvedValue(undefined);
+
+            // Hook into this method to demonstrate the race condition
+            mockRoom.getEncryptionTargetMembers
+                .mockImplementationOnce(async () => {
+                    await firstTargetMembers.promise;
+                    return [mockRoomMember];
+                })
+                .mockImplementationOnce(async () => {
+                    await secondTargetMembers.promise;
+                    return [mockRoomMember];
+                });
+
+            let firstMessageFinished: string | null = null;
+
+            const firstRequest = roomEncryptor.encryptEvent(createMockEvent("Hello"), false);
+            const secondRequest = roomEncryptor.encryptEvent(createMockEvent("Edit of Hello"), false);
+
+            firstRequest.then(() => {
+                if (firstMessageFinished === null) {
+                    firstMessageFinished = "hello";
+                }
+            });
+
+            secondRequest.then(() => {
+                if (firstMessageFinished === null) {
+                    firstMessageFinished = "edit";
+                }
+            });
+
+            // suppose the second getEncryptionTargetMembers call returns first
+            secondTargetMembers.resolve();
+            firstTargetMembers.resolve();
+
+            await Promise.all([firstRequest, secondRequest]);
+
+            expect(firstMessageFinished).toBe("hello");
+        });
+    });
+});
@@ -38,25 +38,117 @@ import { mkEvent } from "../../test-utils/test-utils";
 import { CryptoBackend } from "../../../src/common-crypto/CryptoBackend";
 import { IEventDecryptionResult } from "../../../src/@types/crypto";
 import { OutgoingRequestProcessor } from "../../../src/rust-crypto/OutgoingRequestProcessor";
-import { ServerSideSecretStorage } from "../../../src/secret-storage";
+import {
+    AccountDataClient,
+    AddSecretStorageKeyOpts,
+    SecretStorageCallbacks,
+    ServerSideSecretStorage,
+    ServerSideSecretStorageImpl,
+} from "../../../src/secret-storage";
 import {
    CryptoCallbacks,
    EventShieldColour,
    EventShieldReason,
    ImportRoomKeysOpts,
+    KeyBackupCheck,
    VerificationRequest,
 } from "../../../src/crypto-api";
 import * as testData from "../../test-utils/test-data";
 import { defer } from "../../../src/utils";
+import { logger } from "../../../src/logger";
+import { OutgoingRequestsManager } from "../../../src/rust-crypto/OutgoingRequestsManager";
+import { ClientEvent, ClientEventHandlerMap } from "../../../src/client";
+import { Curve25519AuthData } from "../../../src/crypto-api/keybackup";

 const TEST_USER = "@alice:example.com";
 const TEST_DEVICE_ID = "TEST_DEVICE";

 afterEach(() => {
    fetchMock.reset();
+    jest.restoreAllMocks();
+});
+
+describe("initRustCrypto", () => {
+    function makeTestOlmMachine(): Mocked<OlmMachine> {
+        return {
+            registerRoomKeyUpdatedCallback: jest.fn(),
+            registerUserIdentityUpdatedCallback: jest.fn(),
+            getSecretsFromInbox: jest.fn().mockResolvedValue(["dGhpc2lzYWZha2VzZWNyZXQ="]),
+            deleteSecretsFromInbox: jest.fn(),
+            registerReceiveSecretCallback: jest.fn(),
+            outgoingRequests: jest.fn(),
+        } as unknown as Mocked<OlmMachine>;
+    }
+
+    it("passes through the store params", async () => {
+        const testOlmMachine = makeTestOlmMachine();
+        jest.spyOn(OlmMachine, "initialize").mockResolvedValue(testOlmMachine);
+
+        await initRustCrypto({
+            logger,
+            http: {} as MatrixClient["http"],
+            userId: TEST_USER,
+            deviceId: TEST_DEVICE_ID,
+            secretStorage: {} as ServerSideSecretStorage,
+            cryptoCallbacks: {} as CryptoCallbacks,
+            storePrefix: "storePrefix",
+            storePassphrase: "storePassphrase",
+        });
+
+        expect(OlmMachine.initialize).toHaveBeenCalledWith(
+            expect.anything(),
+            expect.anything(),
+            "storePrefix",
+            "storePassphrase",
+        );
+    });
+
+    it("suppresses the storePassphrase if storePrefix is unset", async () => {
+        const testOlmMachine = makeTestOlmMachine();
+        jest.spyOn(OlmMachine, "initialize").mockResolvedValue(testOlmMachine);
+
+        await initRustCrypto({
+            logger,
+            http: {} as MatrixClient["http"],
+            userId: TEST_USER,
+            deviceId: TEST_DEVICE_ID,
+            secretStorage: {} as ServerSideSecretStorage,
+            cryptoCallbacks: {} as CryptoCallbacks,
+            storePrefix: null,
+            storePassphrase: "storePassphrase",
+        });
+
+        expect(OlmMachine.initialize).toHaveBeenCalledWith(expect.anything(), expect.anything(), undefined, undefined);
+    });
+
+    it("Should get secrets from inbox on start", async () => {
+        const testOlmMachine = makeTestOlmMachine() as OlmMachine;
+        jest.spyOn(OlmMachine, "initialize").mockResolvedValue(testOlmMachine);
+
+        await initRustCrypto({
+            logger,
+            http: {} as MatrixClient["http"],
+            userId: TEST_USER,
+            deviceId: TEST_DEVICE_ID,
+            secretStorage: {} as ServerSideSecretStorage,
+            cryptoCallbacks: {} as CryptoCallbacks,
+            storePrefix: "storePrefix",
+            storePassphrase: "storePassphrase",
+        });
+
+        expect(testOlmMachine.getSecretsFromInbox).toHaveBeenCalledWith("m.megolm_backup.v1");
+    });
 });

 describe("RustCrypto", () => {
+    it("getVersion() should return the current version of the rust sdk and vodozemac", async () => {
+        const rustCrypto = await makeTestRustCrypto();
+        const versions = RustSdkCryptoJs.getVersions();
+        expect(rustCrypto.getVersion()).toBe(
+            `Rust SDK ${versions.matrix_sdk_crypto} (${versions.git_sha}), Vodozemac ${versions.vodozemac}`,
+        );
+    });
+
    describe(".importRoomKeys and .exportRoomKeys", () => {
        let rustCrypto: RustCrypto;

@@ -162,6 +254,7 @@ describe("RustCrypto", () => {
        it("returns sensible values on a default client", async () => {
            const secretStorage = {
                isStored: jest.fn().mockResolvedValue(null),
+                getDefaultKeyId: jest.fn().mockResolvedValue("key"),
            } as unknown as Mocked<ServerSideSecretStorage>;
            const rustCrypto = await makeTestRustCrypto(undefined, undefined, undefined, secretStorage);

@@ -182,6 +275,7 @@ describe("RustCrypto", () => {
        it("throws if `stop` is called mid-call", async () => {
            const secretStorage = {
                isStored: jest.fn().mockResolvedValue(null),
+                getDefaultKeyId: jest.fn().mockResolvedValue(null),
            } as unknown as Mocked<ServerSideSecretStorage>;
            const rustCrypto = await makeTestRustCrypto(undefined, undefined, undefined, secretStorage);

@@ -207,8 +301,67 @@ describe("RustCrypto", () => {
        expect(mockCrossSigningIdentity.bootstrapCrossSigning).toHaveBeenCalledWith({});
    });

+    it("bootstrapSecretStorage creates new backup when requested", async () => {
+        const secretStorageCallbacks = {
+            getSecretStorageKey: async (keys: any, name: string) => {
+                return [[...Object.keys(keys.keys)][0], new Uint8Array(32)];
+            },
+        } as SecretStorageCallbacks;
+        const secretStorage = new ServerSideSecretStorageImpl(new DummyAccountDataClient(), secretStorageCallbacks);
+
+        const outgoingRequestProcessor = {
+            makeOutgoingRequest: jest.fn(),
+        } as unknown as Mocked<OutgoingRequestProcessor>;
+
+        const rustCrypto = await makeTestRustCrypto(
+            new MatrixHttpApi(new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>(), {
+                baseUrl: "http://server/",
+                prefix: "",
+                onlyData: true,
+            }),
+            testData.TEST_USER_ID,
+            undefined,
+            secretStorage,
+        );
+
+        rustCrypto["checkKeyBackupAndEnable"] = async () => {
+            return null;
+        };
+        (rustCrypto["crossSigningIdentity"] as any)["outgoingRequestProcessor"] = outgoingRequestProcessor;
+        const resetKeyBackup = (rustCrypto["resetKeyBackup"] = jest.fn());
+
+        async function createSecretStorageKey() {
+            return {
+                keyInfo: {} as AddSecretStorageKeyOpts,
+                privateKey: new Uint8Array(32),
+            };
+        }
+
+        // create initial secret storage
+        await rustCrypto.bootstrapCrossSigning({ setupNewCrossSigning: true });
+        await rustCrypto.bootstrapSecretStorage({
+            createSecretStorageKey,
+            setupNewSecretStorage: true,
+            setupNewKeyBackup: true,
+        });
+        // check that rustCrypto.resetKeyBackup was called
+        expect(resetKeyBackup.mock.calls).toHaveLength(1);
+
+        // reset secret storage
+        await rustCrypto.bootstrapSecretStorage({
+            createSecretStorageKey,
+            setupNewSecretStorage: true,
+            setupNewKeyBackup: true,
+        });
+        // check that rustCrypto.resetKeyBackup was called again
+        expect(resetKeyBackup.mock.calls).toHaveLength(2);
+    });
+
    it("isSecretStorageReady", async () => {
-        const rustCrypto = await makeTestRustCrypto();
+        const mockSecretStorage = {
+            getDefaultKeyId: jest.fn().mockResolvedValue(null),
+        } as unknown as Mocked<ServerSideSecretStorage>;
+        const rustCrypto = await makeTestRustCrypto(undefined, undefined, undefined, mockSecretStorage);
        await expect(rustCrypto.isSecretStorageReady()).resolves.toBe(false);
    });

@@ -259,7 +412,10 @@ describe("RustCrypto", () => {
                makeOutgoingRequest: jest.fn(),
            } as unknown as Mocked<OutgoingRequestProcessor>;

+            const outgoingRequestsManager = new OutgoingRequestsManager(logger, olmMachine, outgoingRequestProcessor);
+
            rustCrypto = new RustCrypto(
+                logger,
                olmMachine,
                {} as MatrixHttpApi<any>,
                TEST_USER,
@@ -268,6 +424,7 @@ describe("RustCrypto", () => {
                {} as CryptoCallbacks,
            );
            rustCrypto["outgoingRequestProcessor"] = outgoingRequestProcessor;
+            rustCrypto["outgoingRequestsManager"] = outgoingRequestsManager;
        });

        it("should poll for outgoing messages and send them", async () => {
@@ -306,50 +463,6 @@ describe("RustCrypto", () => {
            await awaitCallToMakeOutgoingRequest();
            expect(olmMachine.outgoingRequests).toHaveBeenCalledTimes(2);
        });
-
-        it("stops looping when stop() is called", async () => {
-            for (let i = 0; i < 5; i++) {
-                outgoingRequestQueue.push([new KeysQueryRequest("1234", "{}")]);
-            }
-
-            let makeRequestPromise = awaitCallToMakeOutgoingRequest();
-
-            rustCrypto.onSyncCompleted({});
-
-            expect(rustCrypto["outgoingRequestLoopRunning"]).toBeTruthy();
-
-            // go a couple of times round the loop
-            let resolveMakeRequest = await makeRequestPromise;
-            makeRequestPromise = awaitCallToMakeOutgoingRequest();
-            resolveMakeRequest();
-
-            resolveMakeRequest = await makeRequestPromise;
-            makeRequestPromise = awaitCallToMakeOutgoingRequest();
-            resolveMakeRequest();
-
-            // a second sync while this is going on shouldn't make any difference
-            rustCrypto.onSyncCompleted({});
-
-            resolveMakeRequest = await makeRequestPromise;
-            outgoingRequestProcessor.makeOutgoingRequest.mockReset();
-            resolveMakeRequest();
-
-            // now stop...
-            rustCrypto.stop();
-
-            // which should (eventually) cause the loop to stop with no further calls to outgoingRequests
-            olmMachine.outgoingRequests.mockReset();
-
-            await new Promise((resolve) => {
-                setTimeout(resolve, 100);
-            });
-            expect(rustCrypto["outgoingRequestLoopRunning"]).toBeFalsy();
-            expect(outgoingRequestProcessor.makeOutgoingRequest).not.toHaveBeenCalled();
-            expect(olmMachine.outgoingRequests).not.toHaveBeenCalled();
-
-            // we sent three, so there should be 2 left
-            expect(outgoingRequestQueue.length).toEqual(2);
-        });
    });

    describe(".getEventEncryptionInfo", () => {
@@ -371,7 +484,7 @@ describe("RustCrypto", () => {
                decryptEvent: () =>
                    ({
                        senderCurve25519Key: "1234",
-                    } as IEventDecryptionResult),
+                    }) as IEventDecryptionResult,
            } as unknown as CryptoBackend;
            await event.attemptDecryption(mockCryptoBackend);

@@ -389,6 +502,7 @@ describe("RustCrypto", () => {
                getRoomEventEncryptionInfo: jest.fn(),
            } as unknown as Mocked<RustSdkCryptoJs.OlmMachine>;
            rustCrypto = new RustCrypto(
+                logger,
                olmMachine,
                {} as MatrixClient["http"],
                TEST_USER,
@@ -398,10 +512,6 @@ describe("RustCrypto", () => {
            );
        });

-        afterEach(() => {
-            jest.restoreAllMocks();
-        });
-
        async function makeEncryptedEvent(): Promise<MatrixEvent> {
            const encryptedEvent = mkEvent({
                event: true,
@@ -414,7 +524,7 @@ describe("RustCrypto", () => {
                decryptEvent: () =>
                    ({
                        clearEvent: { content: { body: "1234" } },
-                    } as unknown as IEventDecryptionResult),
+                    }) as unknown as IEventDecryptionResult,
            } as unknown as CryptoBackend;
            await encryptedEvent.attemptDecryption(mockCryptoBackend);
            return encryptedEvent;
@@ -427,6 +537,26 @@ describe("RustCrypto", () => {
            expect(olmMachine.getRoomEventEncryptionInfo).not.toHaveBeenCalled();
        });

+        it("should handle decryption failures", async () => {
+            const event = mkEvent({
+                event: true,
+                type: "m.room.encrypted",
+                content: { algorithm: "fake_alg" },
+                room: "!room:id",
+            });
+            event.event.event_id = "$event:id";
+            const mockCryptoBackend = {
+                decryptEvent: () => {
+                    throw new Error("UISI");
+                },
+            };
+            await event.attemptDecryption(mockCryptoBackend as unknown as CryptoBackend);
+
+            const res = await rustCrypto.getEncryptionInfoForEvent(event);
+            expect(res).toBe(null);
+            expect(olmMachine.getRoomEventEncryptionInfo).not.toHaveBeenCalled();
+        });
+
        it("passes the event into the OlmMachine", async () => {
            const encryptedEvent = await makeEncryptedEvent();
            const res = await rustCrypto.getEncryptionInfoForEvent(encryptedEvent);
@@ -447,7 +577,7 @@ describe("RustCrypto", () => {
            [RustSdkCryptoJs.ShieldColor.Red, EventShieldColour.RED],
        ])("gets the right shield color (%i)", async (rustShield, expectedShield) => {
            const mockEncryptionInfo = {
-                shieldState: jest.fn().mockReturnValue({ color: rustShield, message: null }),
+                shieldState: jest.fn().mockReturnValue({ color: rustShield, message: undefined }),
            } as unknown as RustSdkCryptoJs.EncryptionInfo;
            olmMachine.getRoomEventEncryptionInfo.mockResolvedValue(mockEncryptionInfo);

@@ -458,7 +588,7 @@ describe("RustCrypto", () => {
        });

        it.each([
-            [null, null],
+            [undefined, null],
            ["Encrypted by an unverified user.", EventShieldReason.UNVERIFIED_IDENTITY],
            ["Encrypted by a device not verified by its owner.", EventShieldReason.UNSIGNED_DEVICE],
            [
@@ -567,6 +697,7 @@ describe("RustCrypto", () => {
                getDevice: jest.fn(),
            } as unknown as Mocked<RustSdkCryptoJs.OlmMachine>;
            rustCrypto = new RustCrypto(
+                logger,
                olmMachine,
                {} as MatrixClient["http"],
                TEST_USER,
@@ -578,6 +709,7 @@ describe("RustCrypto", () => {

        it("should call getDevice", async () => {
            olmMachine.getDevice.mockResolvedValue({
+                free: jest.fn(),
                isCrossSigningTrusted: jest.fn().mockReturnValue(false),
                isLocallyTrusted: jest.fn().mockReturnValue(false),
                isCrossSignedByOwner: jest.fn().mockReturnValue(false),
@@ -670,8 +802,8 @@ describe("RustCrypto", () => {
            // Expect the private key to be an Uint8Array with a length of 32
            expect(recoveryKey.privateKey).toBeInstanceOf(Uint8Array);
            expect(recoveryKey.privateKey.length).toBe(32);
-            // Expect keyInfo to be empty
-            expect(Object.keys(recoveryKey.keyInfo!).length).toBe(0);
+            // Expect passphrase info to be absent
+            expect(recoveryKey.keyInfo?.passphrase).toBeUndefined();
        });

        it("should create a recovery key with password", async () => {
@@ -691,11 +823,6 @@ describe("RustCrypto", () => {
    it("should wait for a keys/query before returning devices", async () => {
        jest.useFakeTimers();

-        const mockHttpApi = new MatrixHttpApi(new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>(), {
-            baseUrl: "http://server/",
-            prefix: "",
-            onlyData: true,
-        });
        fetchMock.post("path:/_matrix/client/v3/keys/upload", { one_time_key_counts: {} });
        fetchMock.post("path:/_matrix/client/v3/keys/query", {
            device_keys: {
@@ -705,7 +832,7 @@ describe("RustCrypto", () => {
            },
        });

-        const rustCrypto = await makeTestRustCrypto(mockHttpApi, testData.TEST_USER_ID);
+        const rustCrypto = await makeTestRustCrypto(makeMatrixHttpApi(), testData.TEST_USER_ID);

        // an attempt to fetch the device list should block
        const devicesPromise = rustCrypto.getUserDeviceInfo([testData.TEST_USER_ID]);
@@ -732,10 +859,23 @@ describe("RustCrypto", () => {
        it("can save and restore a key", async () => {
            const key = "testtesttesttesttesttesttesttest";
            const rustCrypto = await makeTestRustCrypto();
-            await rustCrypto.storeSessionBackupPrivateKey(new TextEncoder().encode(key));
+            await rustCrypto.storeSessionBackupPrivateKey(
+                new TextEncoder().encode(key),
+                testData.SIGNED_BACKUP_DATA.version!,
+            );
            const fetched = await rustCrypto.getSessionBackupPrivateKey();
            expect(new TextDecoder().decode(fetched!)).toEqual(key);
        });
+
+        it("fails to save a key if version not provided", async () => {
+            const key = "testtesttesttesttesttesttesttest";
+            const rustCrypto = await makeTestRustCrypto();
+            await expect(() => rustCrypto.storeSessionBackupPrivateKey(new TextEncoder().encode(key))).rejects.toThrow(
+                "storeSessionBackupPrivateKey: version is required",
+            );
+            const fetched = await rustCrypto.getSessionBackupPrivateKey();
+            expect(fetched).toBeNull();
+        });
    });

    describe("getActiveSessionBackupVersion", () => {
@@ -772,6 +912,7 @@ describe("RustCrypto", () => {
                getIdentity: jest.fn(),
            } as unknown as Mocked<RustSdkCryptoJs.OlmMachine>;
            rustCrypto = new RustCrypto(
+                logger,
                olmMachine,
                {} as MatrixClient["http"],
                TEST_USER,
@@ -790,7 +931,7 @@ describe("RustCrypto", () => {
        });

        it("returns a verified UserVerificationStatus when the UserIdentity is verified", async () => {
-            olmMachine.getIdentity.mockResolvedValue({ isVerified: jest.fn().mockReturnValue(true) });
+            olmMachine.getIdentity.mockResolvedValue({ free: jest.fn(), isVerified: jest.fn().mockReturnValue(true) });

            const userVerificationStatus = await rustCrypto.getUserVerificationStatus(testData.TEST_USER_ID);
            expect(userVerificationStatus.isVerified()).toBeTruthy();
@@ -799,8 +940,104 @@ describe("RustCrypto", () => {
            expect(userVerificationStatus.wasCrossSigningVerified()).toBeFalsy();
        });
    });
+
+    describe("key backup", () => {
+        it("is started when rust crypto is created", async () => {
+            // `RustCrypto.checkKeyBackupAndEnable` async call is made in background in the RustCrypto constructor.
+            // We don't have an instance of the rust crypto yet, we spy directly in the prototype.
+            const spyCheckKeyBackupAndEnable = jest
+                .spyOn(RustCrypto.prototype, "checkKeyBackupAndEnable")
+                .mockResolvedValue({} as KeyBackupCheck);
+
+            await makeTestRustCrypto();
+
+            expect(spyCheckKeyBackupAndEnable).toHaveBeenCalled();
+        });
+
+        it("raises KeyBackupStatus event when identify change", async () => {
+            // Return the key backup
+            fetchMock.get("path:/_matrix/client/v3/room_keys/version", testData.SIGNED_BACKUP_DATA);
+
+            const olmMachine = {
+                getIdentity: jest.fn(),
+                // Force the backup to be trusted by the olmMachine
+                verifyBackup: jest.fn().mockResolvedValue({ trusted: jest.fn().mockReturnValue(true) }),
+                isBackupEnabled: jest.fn().mockReturnValue(true),
+                getBackupKeys: jest.fn(),
+                enableBackupV1: jest.fn(),
+            } as unknown as Mocked<RustSdkCryptoJs.OlmMachine>;
+
+            const rustCrypto = new RustCrypto(
+                logger,
+                olmMachine,
+                makeMatrixHttpApi(),
+                testData.TEST_USER_ID,
+                testData.TEST_DEVICE_ID,
+                {} as ServerSideSecretStorage,
+                {} as CryptoCallbacks,
+            );
+
+            // Wait for the key backup to be available
+            const keyBackupStatusPromise = new Promise<boolean>((resolve) =>
+                rustCrypto.once(CryptoEvent.KeyBackupStatus, resolve),
+            );
+            await rustCrypto.onUserIdentityUpdated(new RustSdkCryptoJs.UserId(testData.TEST_USER_ID));
+            expect(await keyBackupStatusPromise).toBe(true);
+        });
+
+        it("does not back up keys that came from backup", async () => {
+            const rustCrypto = await makeTestRustCrypto();
+            const olmMachine: OlmMachine = rustCrypto["olmMachine"];
+
+            await olmMachine.enableBackupV1(
+                (testData.SIGNED_BACKUP_DATA.auth_data as Curve25519AuthData).public_key,
+                testData.SIGNED_BACKUP_DATA.version!,
+            );
+
+            // we import two keys: one "from backup", and one "from export"
+            const [backedUpRoomKey, exportedRoomKey] = testData.MEGOLM_SESSION_DATA_ARRAY;
+            await rustCrypto.importBackedUpRoomKeys([backedUpRoomKey]);
+            await rustCrypto.importRoomKeys([exportedRoomKey]);
+
+            // we ask for the keys that should be backed up
+            const roomKeysRequest = await olmMachine.backupRoomKeys();
+            expect(roomKeysRequest).toBeTruthy();
+            const roomKeys = JSON.parse(roomKeysRequest!.body);
+
+            // we expect that the key "from export" is present
+            expect(roomKeys).toMatchObject({
+                rooms: {
+                    [exportedRoomKey.room_id]: {
+                        sessions: {
+                            [exportedRoomKey.session_id]: {},
+                        },
+                    },
+                },
+            });
+
+            // we expect that the key "from backup" is not present
+            expect(roomKeys).not.toMatchObject({
+                rooms: {
+                    [backedUpRoomKey.room_id]: {
+                        sessions: {
+                            [backedUpRoomKey.session_id]: {},
+                        },
+                    },
+                },
+            });
+        });
+    });
 });

+/** Build a MatrixHttpApi instance */
+function makeMatrixHttpApi(): MatrixHttpApi<IHttpOpts & { onlyData: true }> {
+    return new MatrixHttpApi(new TypedEventEmitter<HttpApiEvent, HttpApiEventHandlerMap>(), {
+        baseUrl: "http://server/",
+        prefix: "",
+        onlyData: true,
+    });
+}
+
 /** build a basic RustCrypto instance for testing
 *
 * just provides default arguments for initRustCrypto()
@@ -812,5 +1049,49 @@ async function makeTestRustCrypto(
    secretStorage: ServerSideSecretStorage = {} as ServerSideSecretStorage,
    cryptoCallbacks: CryptoCallbacks = {} as CryptoCallbacks,
 ): Promise<RustCrypto> {
-    return await initRustCrypto(http, userId, deviceId, secretStorage, cryptoCallbacks, null);
+    return await initRustCrypto({
+        logger,
+        http,
+        userId,
+        deviceId,
+        secretStorage,
+        cryptoCallbacks,
+        storePrefix: null,
+        storePassphrase: undefined,
+    });
+}
+
+/** emulate account data, storing in memory
+ */
+class DummyAccountDataClient
+    extends TypedEventEmitter<ClientEvent.AccountData, ClientEventHandlerMap>
+    implements AccountDataClient
+{
+    private storage: Map<string, any> = new Map();
+
+    public constructor() {
+        super();
+    }
+
+    public async getAccountDataFromServer<T extends Record<string, any>>(eventType: string): Promise<T | null> {
+        const ret = this.storage.get(eventType);
+
+        if (eventType) {
+            return ret as T;
+        } else {
+            return null;
+        }
+    }
+
+    public async setAccountData(eventType: string, content: any): Promise<{}> {
+        this.storage.set(eventType, content);
+        this.emit(
+            ClientEvent.AccountData,
+            new MatrixEvent({
+                content,
+                type: eventType,
+            }),
+        );
+        return {};
+    }
 }
@@ -14,7 +14,10 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */

-import { secretStorageContainsCrossSigningKeys } from "../../../src/rust-crypto/secret-storage";
+import {
+    secretStorageCanAccessSecrets,
+    secretStorageContainsCrossSigningKeys,
+} from "../../../src/rust-crypto/secret-storage";
 import { ServerSideSecretStorage } from "../../../src/secret-storage";

 describe("secret-storage", () => {
@@ -22,6 +25,7 @@ describe("secret-storage", () => {
        it("should return false when the master cross-signing key is not stored in secret storage", async () => {
            const secretStorage = {
                isStored: jest.fn().mockReturnValue(false),
+                getDefaultKeyId: jest.fn().mockResolvedValue("SFQ3TbqGOdaaRVfxHtNkn0tvhx0rVj9S"),
            } as unknown as ServerSideSecretStorage;

            const result = await secretStorageContainsCrossSigningKeys(secretStorage);
@@ -35,6 +39,7 @@ describe("secret-storage", () => {
                    if (type === "m.cross_signing.master") return { secretStorageKey: {} };
                    else return { secretStorageKey2: {} };
                },
+                getDefaultKeyId: jest.fn().mockResolvedValue("SFQ3TbqGOdaaRVfxHtNkn0tvhx0rVj9S"),
            } as unknown as ServerSideSecretStorage;

            const result = await secretStorageContainsCrossSigningKeys(secretStorage);
@@ -51,19 +56,73 @@ describe("secret-storage", () => {
                        return { secretStorageKey2: {} };
                    }
                },
+                getDefaultKeyId: jest.fn().mockResolvedValue("secretStorageKey"),
            } as unknown as ServerSideSecretStorage;

            const result = await secretStorageContainsCrossSigningKeys(secretStorage);
            expect(result).toBeFalsy();
        });

-        it("should return true when there is shared secret storage key between master, user signing and self signing keys", async () => {
+        it("should return true when master, user signing and self signing keys are all encrypted with default key", async () => {
            const secretStorage = {
                isStored: jest.fn().mockReturnValue({ secretStorageKey: {} }),
+                getDefaultKeyId: jest.fn().mockResolvedValue("secretStorageKey"),
            } as unknown as ServerSideSecretStorage;

            const result = await secretStorageContainsCrossSigningKeys(secretStorage);
            expect(result).toBeTruthy();
        });
+
+        it("should return false when master, user signing and self signing keys are all encrypted with a non-default key", async () => {
+            const secretStorage = {
+                isStored: jest.fn().mockResolvedValue({ defaultKey: {} }),
+                getDefaultKeyId: jest.fn().mockResolvedValue("anotherCommonKey"),
+            } as unknown as ServerSideSecretStorage;
+
+            const result = await secretStorageContainsCrossSigningKeys(secretStorage);
+            expect(result).toBeFalsy();
+        });
+    });
+
+    it("Check canAccessSecrets", async () => {
+        const secretStorage = {
+            isStored: jest.fn((secretName) => {
+                if (secretName == "secretA") {
+                    return { aaaa: {} };
+                } else if (secretName == "secretB") {
+                    return { bbbb: {} };
+                } else if (secretName == "secretC") {
+                    return { cccc: {} };
+                } else if (secretName == "secretD") {
+                    return { aaaa: {} };
+                } else if (secretName == "secretE") {
+                    return { aaaa: {}, bbbb: {} };
+                } else {
+                    null;
+                }
+            }),
+            getDefaultKeyId: jest.fn().mockResolvedValue("aaaa"),
+        } as unknown as ServerSideSecretStorage;
+
+        expect(await secretStorageCanAccessSecrets(secretStorage, ["secretE"])).toStrictEqual(true);
+        expect(await secretStorageCanAccessSecrets(secretStorage, ["secretA"])).toStrictEqual(true);
+        expect(await secretStorageCanAccessSecrets(secretStorage, ["secretC"])).toStrictEqual(false);
+        expect(await secretStorageCanAccessSecrets(secretStorage, ["secretA", "secretD"])).toStrictEqual(true);
+        expect(await secretStorageCanAccessSecrets(secretStorage, ["secretA", "secretC"])).toStrictEqual(false);
+        expect(await secretStorageCanAccessSecrets(secretStorage, ["secretC", "secretA"])).toStrictEqual(false);
+        expect(await secretStorageCanAccessSecrets(secretStorage, ["secretA", "secretD", "secretB"])).toStrictEqual(
+            false,
+        );
+        expect(await secretStorageCanAccessSecrets(secretStorage, ["secretA", "secretD", "Unknown"])).toStrictEqual(
+            false,
+        );
+
+        expect(await secretStorageCanAccessSecrets(secretStorage, ["secretA", "secretD", "secretE"])).toStrictEqual(
+            true,
+        );
+        expect(
+            await secretStorageCanAccessSecrets(secretStorage, ["secretA", "secretC", "secretD", "secretE"]),
+        ).toStrictEqual(false);
+        expect(await secretStorageCanAccessSecrets(secretStorage, [])).toStrictEqual(true);
    });
 });
@@ -62,9 +62,13 @@ describe("VerificationRequest", () => {

    describe("startVerification", () => {
        let request: RustVerificationRequest;
+        let machine: Mocked<RustSdkCryptoJs.OlmMachine>;
+        let inner: Mocked<RustSdkCryptoJs.VerificationRequest>;

        beforeEach(() => {
-            request = makeTestRequest();
+            inner = makeMockedInner();
+            machine = { getDevice: jest.fn() } as unknown as Mocked<RustSdkCryptoJs.OlmMachine>;
+            request = makeTestRequest(inner, machine);
        });

        it("does not permit methods other than SAS", async () => {
@@ -73,7 +77,15 @@ describe("VerificationRequest", () => {
            );
        });

+        it("raises an error if the other device is unknown", async () => {
+            await expect(request.startVerification("m.sas.v1")).rejects.toThrow(
+                "startVerification(): other device is unknown",
+            );
+        });
+
        it("raises an error if starting verification does not produce a verifier", async () => {
+            jest.spyOn(inner, "otherDeviceId", "get").mockReturnValue(new RustSdkCryptoJs.DeviceId("other_device"));
+            machine.getDevice.mockResolvedValue({} as RustSdkCryptoJs.Device);
            await expect(request.startVerification("m.sas.v1")).rejects.toThrow(
                "Still no verifier after startSas() call",
            );
@@ -118,11 +130,13 @@ describe("isVerificationEvent", () => {
 /** build a RustVerificationRequest with default parameters */
 function makeTestRequest(
    inner?: RustSdkCryptoJs.VerificationRequest,
+    olmMachine?: RustSdkCryptoJs.OlmMachine,
    outgoingRequestProcessor?: OutgoingRequestProcessor,
 ): RustVerificationRequest {
    inner ??= makeMockedInner();
+    olmMachine ??= {} as RustSdkCryptoJs.OlmMachine;
    outgoingRequestProcessor ??= {} as OutgoingRequestProcessor;
-    return new RustVerificationRequest(inner, outgoingRequestProcessor, []);
+    return new RustVerificationRequest(olmMachine, inner, outgoingRequestProcessor, []);
 }

 /** Mock up a rust-side VerificationRequest */
@@ -133,5 +147,8 @@ function makeMockedInner(): Mocked<RustSdkCryptoJs.VerificationRequest> {
        phase: jest.fn().mockReturnValue(RustSdkCryptoJs.VerificationRequestPhase.Created),
        isPassive: jest.fn().mockReturnValue(false),
        timeRemainingMillis: jest.fn(),
+        get otherDeviceId() {
+            return undefined;
+        },
    } as unknown as Mocked<RustSdkCryptoJs.VerificationRequest>;
 }
--- a/Show More
+++ b/Show More