diff --git a/.github/workflows/docs-pr-netlify.yaml b/.github/workflows/docs-pr-netlify.yaml
index d1b789c8d0..8a06ad6362 100644
--- a/.github/workflows/docs-pr-netlify.yaml
+++ b/.github/workflows/docs-pr-netlify.yaml
@@ -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@20319c5641d495c8a52e688b7dc5fada6c3a9fbc # v8
+        uses: dawidd6/action-download-artifact@07ab29fd4a977ae4d2b275087cf67563dfdf0295 # v9
         with:
           workflow: docs-pr.yaml
           run_id: ${{ github.event.workflow_run.id }}
diff --git a/.github/workflows/docs-pr.yaml b/.github/workflows/docs-pr.yaml
index 1b416407d8..616ef0f9cf 100644
--- a/.github/workflows/docs-pr.yaml
+++ b/.github/workflows/docs-pr.yaml
@@ -24,7 +24,7 @@ jobs:
           mdbook-version: '0.4.17'
 
       - name: Setup python
-        uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+        uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: "3.x"
 
@@ -39,7 +39,7 @@ jobs:
           cp book/welcome_and_overview.html book/index.html
 
       - name: Upload Artifact
-        uses: actions/upload-artifact@4cec3d8aa04e39d1a68397de0c4cd6fb9dce8ec1 # v4.6.1
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         with:
           name: book
           path: book
diff --git a/.github/workflows/docs.yaml b/.github/workflows/docs.yaml
index 121c29571a..05ae608d06 100644
--- a/.github/workflows/docs.yaml
+++ b/.github/workflows/docs.yaml
@@ -64,7 +64,7 @@ jobs:
         run: echo 'window.SYNAPSE_VERSION = "${{ needs.pre.outputs.branch-version }}";' > ./docs/website_files/version.js
 
       - name: Setup python
-        uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+        uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: "3.x"
 
diff --git a/.github/workflows/latest_deps.yml b/.github/workflows/latest_deps.yml
index b7c1b727c9..e7378ec0d3 100644
--- a/.github/workflows/latest_deps.yml
+++ b/.github/workflows/latest_deps.yml
@@ -86,7 +86,7 @@ jobs:
             -e POSTGRES_PASSWORD=postgres \
             -e POSTGRES_INITDB_ARGS="--lc-collate C --lc-ctype C --encoding UTF8" \
             postgres:${{ matrix.postgres-version }}
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: "3.x"
       - run: pip install .[all,test]
@@ -164,7 +164,7 @@ jobs:
         if: ${{ always() }}
         run: /sytest/scripts/tap_to_gha.pl /logs/results.tap
       - name: Upload SyTest logs
-        uses: actions/upload-artifact@4cec3d8aa04e39d1a68397de0c4cd6fb9dce8ec1 # v4.6.1
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         if: ${{ always() }}
         with:
           name: Sytest Logs - ${{ job.status }} - (${{ join(matrix.*, ', ') }})
diff --git a/.github/workflows/poetry_lockfile.yaml b/.github/workflows/poetry_lockfile.yaml
index b3251d379e..31b9147e98 100644
--- a/.github/workflows/poetry_lockfile.yaml
+++ b/.github/workflows/poetry_lockfile.yaml
@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: '3.x'
       - run: pip install tomli
diff --git a/.github/workflows/release-artifacts.yml b/.github/workflows/release-artifacts.yml
index 9985084a73..573264229f 100644
--- a/.github/workflows/release-artifacts.yml
+++ b/.github/workflows/release-artifacts.yml
@@ -28,7 +28,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: '3.x'
       - id: set-distros
@@ -66,7 +66,7 @@ jobs:
           install: true
 
       - name: Set up docker layer caching
-        uses: actions/cache@d4323d4df104b026a6aa633fdb11d772146be0bf # v4.2.2
+        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: /tmp/.buildx-cache
           key: ${{ runner.os }}-buildx-${{ github.sha }}
@@ -74,7 +74,7 @@ jobs:
             ${{ runner.os }}-buildx-
 
       - name: Set up python
-        uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+        uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: '3.x'
 
@@ -101,7 +101,7 @@ jobs:
           echo "ARTIFACT_NAME=${DISTRO#*:}" >> "$GITHUB_OUTPUT"
 
       - name: Upload debs as artifacts
-        uses: actions/upload-artifact@4cec3d8aa04e39d1a68397de0c4cd6fb9dce8ec1 # v4.6.1
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         with:
           name: debs-${{ steps.artifact-name.outputs.ARTIFACT_NAME }}
           path: debs/*
@@ -132,7 +132,7 @@ jobs:
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
 
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           # setup-python@v4 doesn't impose a default python version. Need to use 3.x
           # here, because `python` on osx points to Python 2.7.
@@ -165,7 +165,7 @@ jobs:
           CARGO_NET_GIT_FETCH_WITH_CLI: true
           CIBW_ENVIRONMENT_PASS_LINUX: CARGO_NET_GIT_FETCH_WITH_CLI
 
-      - uses: actions/upload-artifact@4cec3d8aa04e39d1a68397de0c4cd6fb9dce8ec1 # v4.6.1
+      - uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         with:
           name: Wheel-${{ matrix.os }}-${{ matrix.arch }}
           path: ./wheelhouse/*.whl
@@ -177,7 +177,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: '3.10'
 
@@ -186,7 +186,7 @@ jobs:
       - name: Build sdist
         run: python -m build --sdist
 
-      - uses: actions/upload-artifact@4cec3d8aa04e39d1a68397de0c4cd6fb9dce8ec1 # v4.6.1
+      - uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         with:
           name: Sdist
           path: dist/*.tar.gz
@@ -203,7 +203,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Download all workflow run artifacts
-        uses: actions/download-artifact@b14cf4c92620c250e1c074ab0a5800e37df86765 # v4.2.0
+        uses: actions/download-artifact@95815c38cf2ff2164869cbab79da8d1f422bc89e # v4.2.1
       - name: Build a tarball for the debs
         # We need to merge all the debs uploads into one folder, then compress
         # that.
diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index ff83d6e365..bb2e80a908 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -102,7 +102,7 @@ jobs:
 
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: "3.x"
       - run: "pip install 'click==8.1.1' 'GitPython>=3.1.20'"
@@ -112,7 +112,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: "3.x"
       - run: .ci/scripts/check_lockfile.py
@@ -167,7 +167,7 @@ jobs:
       # Cribbed from
       # https://github.com/AustinScola/mypy-cache-github-action/blob/85ea4f2972abed39b33bd02c36e341b28ca59213/src/restore.ts#L10-L17
       - name: Restore/persist mypy's cache
-        uses: actions/cache@d4323d4df104b026a6aa633fdb11d772146be0bf # v4.2.2
+        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
           path: |
             .mypy_cache
@@ -192,7 +192,7 @@ jobs:
         with:
           ref: ${{ github.event.pull_request.head.sha }}
           fetch-depth: 0
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: "3.x"
       - run: "pip install 'towncrier>=18.6.0rc1'"
@@ -279,7 +279,7 @@ jobs:
     if: ${{ needs.changes.outputs.linting_readme == 'true' }}
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: "3.x"
       - run: "pip install rstcheck"
@@ -327,7 +327,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@11bd71901bbe5b1630ceea73d27597364c9af683 # v4.2.2
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: "3.x"
       - id: get-matrix
@@ -414,7 +414,7 @@ jobs:
           sudo apt-get -qq install build-essential libffi-dev python3-dev \
             libxml2-dev libxslt-dev xmlsec1 zlib1g-dev libjpeg-dev libwebp-dev
 
-      - uses: actions/setup-python@42375524e23c412d93fb67b49958b491fce71c38 # v5.4.0
+      - uses: actions/setup-python@8d9ed9ac5c53483de85588cdf95a591a75ab9f55 # v5.5.0
         with:
           python-version: '3.9'
 
@@ -529,7 +529,7 @@ jobs:
         if: ${{ always() }}
         run: /sytest/scripts/tap_to_gha.pl /logs/results.tap
       - name: Upload SyTest logs
-        uses: actions/upload-artifact@4cec3d8aa04e39d1a68397de0c4cd6fb9dce8ec1 # v4.6.1
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         if: ${{ always() }}
         with:
           name: Sytest Logs - ${{ job.status }} - (${{ join(matrix.job.*, ', ') }})
@@ -627,7 +627,7 @@ jobs:
           PGPASSWORD: postgres
           PGDATABASE: postgres
       - name: "Upload schema differences"
-        uses: actions/upload-artifact@4cec3d8aa04e39d1a68397de0c4cd6fb9dce8ec1 # v4.6.1
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         if: ${{ failure() && !cancelled() && steps.run_tester_script.outcome == 'failure' }}
         with:
           name: Schema dumps
diff --git a/.github/workflows/triage_labelled.yml b/.github/workflows/triage_labelled.yml
index c08c674c88..feab5906e0 100644
--- a/.github/workflows/triage_labelled.yml
+++ b/.github/workflows/triage_labelled.yml
@@ -11,7 +11,7 @@ jobs:
     if: >
       contains(github.event.issue.labels.*.name, 'X-Needs-Info')
     steps:
-      - uses: actions/add-to-project@f5473ace9aeee8b97717b281e26980aa5097023f # main (v1.0.2 + 10 commits)
+      - uses: actions/add-to-project@280af8ae1f83a494cfad2cb10f02f6d13529caa9 # main (v1.0.2 + 10 commits)
         id: add_project
         with:
           project-url: "https://github.com/orgs/matrix-org/projects/67"
diff --git a/.github/workflows/twisted_trunk.yml b/.github/workflows/twisted_trunk.yml
index aac1e350a2..0176f17401 100644
--- a/.github/workflows/twisted_trunk.yml
+++ b/.github/workflows/twisted_trunk.yml
@@ -138,7 +138,7 @@ jobs:
         if: ${{ always() }}
         run: /sytest/scripts/tap_to_gha.pl /logs/results.tap
       - name: Upload SyTest logs
-        uses: actions/upload-artifact@4cec3d8aa04e39d1a68397de0c4cd6fb9dce8ec1 # v4.6.1
+        uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2
         if: ${{ always() }}
         with:
           name: Sytest Logs - ${{ job.status }} - (${{ join(matrix.*, ', ') }})
diff --git a/CHANGES.md b/CHANGES.md
index 0176c6e45d..35c3f22aaa 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,54 @@
+# Synapse 1.128.0rc1 (2025-04-01)
+
+### Features
+
+- Add an access token introspection cache to make Matrix Authentication Service integration ([MSC3861](https://github.com/matrix-org/matrix-doc/pull/3861)) more efficient. ([\#18231](https://github.com/element-hq/synapse/issues/18231))
+- Add background job to clear unreferenced state groups. ([\#18254](https://github.com/element-hq/synapse/issues/18254))
+- Hashes of media files are now tracked by Synapse. Media quarantines will now apply to all files with the same hash. ([\#18277](https://github.com/element-hq/synapse/issues/18277), [\#18302](https://github.com/element-hq/synapse/issues/18302), [\#18296](https://github.com/element-hq/synapse/issues/18296))
+
+### Bugfixes
+
+- Add index to sliding sync ([MSC4186](https://github.com/matrix-org/matrix-doc/pull/4186)) membership snapshot table, to fix a performance issue. ([\#18074](https://github.com/element-hq/synapse/issues/18074))
+
+### Updates to the Docker image
+
+- Specify the architecture of installed packages via an APT config option, which is more reliable than appending package names with `:{arch}`. ([\#18271](https://github.com/element-hq/synapse/issues/18271))
+- Always specify base image debian versions with a build argument. ([\#18272](https://github.com/element-hq/synapse/issues/18272))
+- Allow passing arguments to `start_for_complement.sh` (to be sent to `configure_workers_and_start.py`). ([\#18273](https://github.com/element-hq/synapse/issues/18273))
+- Make some improvements to the `prefix-log` script in the workers image. ([\#18274](https://github.com/element-hq/synapse/issues/18274))
+- Use `uv pip` to install `supervisor` in the worker image. ([\#18275](https://github.com/element-hq/synapse/issues/18275))
+- Avoid needing to download & use `rsync` in a build layer. ([\#18287](https://github.com/element-hq/synapse/issues/18287))
+
+### Improved Documentation
+
+- Fix how to obtain access token and change naming from riot to element ([\#18225](https://github.com/element-hq/synapse/issues/18225))
+- Correct a small typo in the SSO mapping providers documentation. ([\#18276](https://github.com/element-hq/synapse/issues/18276))
+- Add docs for how to clear out the Poetry wheel cache. ([\#18283](https://github.com/element-hq/synapse/issues/18283))
+
+### Internal Changes
+
+- Add a column `participant` to `room_memberships` table. ([\#18068](https://github.com/element-hq/synapse/issues/18068))
+- Update Poetry to 2.1.1, including updating the lock file version. ([\#18251](https://github.com/element-hq/synapse/issues/18251))
+- Pin GitHub Actions dependencies by commit hash. ([\#18255](https://github.com/element-hq/synapse/issues/18255))
+- Add DB delta to remove the old state group deletion job. ([\#18284](https://github.com/element-hq/synapse/issues/18284))
+
+
+
+### Updates to locked dependencies
+
+* Bump actions/add-to-project from f5473ace9aeee8b97717b281e26980aa5097023f to 280af8ae1f83a494cfad2cb10f02f6d13529caa9. ([\#18303](https://github.com/element-hq/synapse/issues/18303))
+* Bump actions/cache from 4.2.2 to 4.2.3. ([\#18266](https://github.com/element-hq/synapse/issues/18266))
+* Bump actions/download-artifact from 4.2.0 to 4.2.1. ([\#18268](https://github.com/element-hq/synapse/issues/18268))
+* Bump actions/setup-python from 5.4.0 to 5.5.0. ([\#18298](https://github.com/element-hq/synapse/issues/18298))
+* Bump actions/upload-artifact from 4.6.1 to 4.6.2. ([\#18304](https://github.com/element-hq/synapse/issues/18304))
+* Bump authlib from 1.4.1 to 1.5.1. ([\#18306](https://github.com/element-hq/synapse/issues/18306))
+* Bump dawidd6/action-download-artifact from 8 to 9. ([\#18204](https://github.com/element-hq/synapse/issues/18204))
+* Bump jinja2 from 3.1.5 to 3.1.6. ([\#18223](https://github.com/element-hq/synapse/issues/18223))
+* Bump log from 0.4.26 to 0.4.27. ([\#18267](https://github.com/element-hq/synapse/issues/18267))
+* Bump phonenumbers from 8.13.50 to 9.0.2. ([\#18299](https://github.com/element-hq/synapse/issues/18299))
+* Bump pygithub from 2.5.0 to 2.6.1. ([\#18243](https://github.com/element-hq/synapse/issues/18243))
+* Bump pyo3-log from 0.12.1 to 0.12.2. ([\#18269](https://github.com/element-hq/synapse/issues/18269))
+
 # Synapse 1.127.1 (2025-03-26)
 
 ## Security
diff --git a/Cargo.lock b/Cargo.lock
index 20110694a5..1b17e9910a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -316,9 +316,9 @@ dependencies = [
 
 [[package]]
 name = "pyo3-log"
-version = "0.12.1"
+version = "0.12.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "be5bb22b77965a7b5394e9aae9897a0607b51df5167561ffc3b02643b4200bc7"
+checksum = "4b78e4983ba15bc62833a0e0941d965bc03690163f1127864f1408db25063466"
 dependencies = [
  "arc-swap",
  "log",
diff --git a/changelog.d/18068.misc b/changelog.d/18068.misc
deleted file mode 100644
index af6f78f549..0000000000
--- a/changelog.d/18068.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add a column `participant` to `room_memberships` table.
\ No newline at end of file
diff --git a/changelog.d/18074.bugfix b/changelog.d/18074.bugfix
deleted file mode 100644
index 03e0b95988..0000000000
--- a/changelog.d/18074.bugfix
+++ /dev/null
@@ -1 +0,0 @@
-Add index to sliding sync membership snapshot table, to fix a performance issue.
\ No newline at end of file
diff --git a/changelog.d/18133.misc b/changelog.d/18133.misc
new file mode 100644
index 0000000000..151ceb2cab
--- /dev/null
+++ b/changelog.d/18133.misc
@@ -0,0 +1 @@
+Disable statement timeout during room purge.
diff --git a/changelog.d/18225.doc b/changelog.d/18225.doc
deleted file mode 100644
index 854e275120..0000000000
--- a/changelog.d/18225.doc
+++ /dev/null
@@ -1 +0,0 @@
-Fix how to obtain access token and change naming from riot to element
diff --git a/changelog.d/18251.misc b/changelog.d/18251.misc
deleted file mode 100644
index 3b557a06c4..0000000000
--- a/changelog.d/18251.misc
+++ /dev/null
@@ -1 +0,0 @@
-Update Poetry to 2.1.1, including updating the lock file version.
\ No newline at end of file
diff --git a/changelog.d/18254.feature b/changelog.d/18254.feature
deleted file mode 100644
index 62e1b79a15..0000000000
--- a/changelog.d/18254.feature
+++ /dev/null
@@ -1 +0,0 @@
-Add background job to clear unreferenced state groups.
diff --git a/changelog.d/18255.misc b/changelog.d/18255.misc
deleted file mode 100644
index 49a5b0e7b6..0000000000
--- a/changelog.d/18255.misc
+++ /dev/null
@@ -1 +0,0 @@
-Pin GitHub Actions dependencies by commit hash.
\ No newline at end of file
diff --git a/changelog.d/18271.docker b/changelog.d/18271.docker
deleted file mode 100644
index fcb2ac1e00..0000000000
--- a/changelog.d/18271.docker
+++ /dev/null
@@ -1 +0,0 @@
-Specify the architecture of installed packages via an APT config option, which is more reliable than appending package names with ":{arch}".
diff --git a/changelog.d/18272.docker b/changelog.d/18272.docker
deleted file mode 100644
index ceec619b6c..0000000000
--- a/changelog.d/18272.docker
+++ /dev/null
@@ -1 +0,0 @@
-Always specify base image debian versions with a build argument.
diff --git a/changelog.d/18273.docker b/changelog.d/18273.docker
deleted file mode 100644
index 1da0c3efb1..0000000000
--- a/changelog.d/18273.docker
+++ /dev/null
@@ -1 +0,0 @@
-Allow passing arguments to start_for_complement.sh (to be sent to configure_workers_and_start.py).
diff --git a/changelog.d/18276.doc b/changelog.d/18276.doc
deleted file mode 100644
index cacf6daf76..0000000000
--- a/changelog.d/18276.doc
+++ /dev/null
@@ -1 +0,0 @@
-Correct a small typo in the SSO mapping providers documentation.
\ No newline at end of file
diff --git a/changelog.d/18277.feature b/changelog.d/18277.feature
deleted file mode 100644
index 3604e732d5..0000000000
--- a/changelog.d/18277.feature
+++ /dev/null
@@ -1 +0,0 @@
-Hashes of media files are now tracked by Synapse. Media quarantines will now apply to all files with the same hash.
\ No newline at end of file
diff --git a/changelog.d/18283.doc b/changelog.d/18283.doc
deleted file mode 100644
index 77fa08fa6b..0000000000
--- a/changelog.d/18283.doc
+++ /dev/null
@@ -1 +0,0 @@
-Add docs for how to clear out the Poetry wheel cache.
diff --git a/changelog.d/18284.misc b/changelog.d/18284.misc
deleted file mode 100644
index 69610adc65..0000000000
--- a/changelog.d/18284.misc
+++ /dev/null
@@ -1 +0,0 @@
-Add DB delta to remove the old state group deletion job.
diff --git a/changelog.d/18294.docker b/changelog.d/18294.docker
new file mode 100644
index 0000000000..cc40ca90c0
--- /dev/null
+++ b/changelog.d/18294.docker
@@ -0,0 +1 @@
+Optimize the build of the complement-synapse image.
diff --git a/debian/changelog b/debian/changelog
index 645001ca52..6e338ecd74 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,8 +1,9 @@
-matrix-synapse-py3 (1.128.0~rc1+nmu1) UNRELEASED; urgency=medium
+matrix-synapse-py3 (1.128.0~rc1) stable; urgency=medium
 
   * Update Poetry to 2.1.1.
+  * New synapse release 1.128.0rc1.
 
- -- Synapse Packaging team <packages@matrix.org>  Wed, 19 Mar 2025 17:38:49 +0000
+ -- Synapse Packaging team <packages@matrix.org>  Tue, 01 Apr 2025 14:35:33 +0000
 
 matrix-synapse-py3 (1.127.1) stable; urgency=medium
 
diff --git a/docker/Dockerfile b/docker/Dockerfile
index 54aa355370..15c458fa28 100644
--- a/docker/Dockerfile
+++ b/docker/Dockerfile
@@ -134,7 +134,6 @@ RUN \
   --mount=type=cache,target=/var/cache/apt,sharing=locked \
   --mount=type=cache,target=/var/lib/apt,sharing=locked \
   apt-get update -qq && \
-  apt-get install -y --no-install-recommends rsync && \
   apt-cache depends --recurse --no-recommends --no-suggests --no-conflicts --no-breaks --no-replaces --no-enhances --no-pre-depends \
       curl \
       gosu \
@@ -152,10 +151,6 @@ RUN \
   done
 
 # Extract the debs for each architecture
-# On the runtime image, /lib is a symlink to /usr/lib, so we need to copy the
-# libraries to the right place, else the `COPY` won't work.
-# On amd64, we'll also have a /lib64 folder with ld-linux-x86-64.so.2, which is
-# already present in the runtime image.
 RUN \
   for arch in arm64 amd64; do \
     mkdir -p /install-${arch}/var/lib/dpkg/status.d/ && \
@@ -165,8 +160,6 @@ RUN \
       dpkg --ctrl-tarfile $deb | tar -Ox ./control > /install-${arch}/var/lib/dpkg/status.d/${package_name}; \
       dpkg --extract $deb /install-${arch}; \
     done; \
-    rsync -avr /install-${arch}/lib/ /install-${arch}/usr/lib; \
-    rm -rf /install-${arch}/lib /install-${arch}/lib64; \
   done
 
 
@@ -183,7 +176,14 @@ LABEL org.opencontainers.image.documentation='https://github.com/element-hq/syna
 LABEL org.opencontainers.image.source='https://github.com/element-hq/synapse.git'
 LABEL org.opencontainers.image.licenses='AGPL-3.0-or-later'
 
-COPY --from=runtime-deps /install-${TARGETARCH} /
+# On the runtime image, /lib is a symlink to /usr/lib, so we need to copy the
+# libraries to the right place, else the `COPY` won't work.
+# On amd64, we'll also have a /lib64 folder with ld-linux-x86-64.so.2, which is
+# already present in the runtime image.
+COPY --from=runtime-deps /install-${TARGETARCH}/lib /usr/lib
+COPY --from=runtime-deps /install-${TARGETARCH}/etc /etc
+COPY --from=runtime-deps /install-${TARGETARCH}/usr /usr
+COPY --from=runtime-deps /install-${TARGETARCH}/var /var
 COPY --from=builder /install /usr/local
 COPY ./docker/start.py /start.py
 COPY ./docker/conf /conf
diff --git a/docker/Dockerfile-workers b/docker/Dockerfile-workers
index 3dec4bba05..dd0bf59994 100644
--- a/docker/Dockerfile-workers
+++ b/docker/Dockerfile-workers
@@ -27,10 +27,15 @@ FROM docker.io/library/redis:7-${DEBIAN_VERSION} AS redis_base
 # now build the final image, based on the the regular Synapse docker image
 FROM $FROM
 
-    # Install supervisord with pip instead of apt, to avoid installing a second
+    # Install supervisord with uv pip instead of apt, to avoid installing a second
     # copy of python.
-    RUN --mount=type=cache,target=/root/.cache/pip \
-        pip install supervisor~=4.2
+    # --link-mode=copy silences a warning as uv isn't able to do hardlinks between its cache
+    # (mounted as --mount=type=cache) and the target directory.
+    RUN \
+         --mount=type=bind,from=ghcr.io/astral-sh/uv:0.6.8,source=/uv,target=/uv \
+         --mount=type=cache,target=/root/.cache/uv \
+        /uv pip install --link-mode=copy --prefix="/usr/local" supervisor~=4.2
+
     RUN mkdir -p /etc/supervisor/conf.d
 
     # Copy over redis and nginx
diff --git a/docker/complement/Dockerfile b/docker/complement/Dockerfile
index 3e7f808cc5..dd029c5fbc 100644
--- a/docker/complement/Dockerfile
+++ b/docker/complement/Dockerfile
@@ -25,7 +25,7 @@ FROM $FROM
 RUN adduser --system --uid 999 postgres --home /var/lib/postgresql
 COPY --from=postgres_base /usr/lib/postgresql /usr/lib/postgresql
 COPY --from=postgres_base /usr/share/postgresql /usr/share/postgresql
-RUN mkdir /var/run/postgresql && chown postgres /var/run/postgresql
+COPY --from=postgres_base --chown=postgres /var/run/postgresql /var/run/postgresql
 ENV PATH="${PATH}:/usr/lib/postgresql/13/bin"
 ENV PGDATA=/var/lib/postgresql/data
 
diff --git a/docker/prefix-log b/docker/prefix-log
index 32dddbbfd4..2a38de5686 100755
--- a/docker/prefix-log
+++ b/docker/prefix-log
@@ -10,6 +10,9 @@
 # '-W interactive' is a `mawk` extension which disables buffering on stdout and sets line-buffered reads on
 # stdin. The effect is that the output is flushed after each line, rather than being batched, which helps reduce
 # confusion due to to interleaving of the different processes.
-exec 1> >(awk -W interactive '{print "'"${SUPERVISOR_PROCESS_NAME}"' | "$0 }' >&1)
-exec 2> >(awk -W interactive '{print "'"${SUPERVISOR_PROCESS_NAME}"' | "$0 }' >&2)
+prefixer() {
+    mawk -W interactive '{printf("%s | %s\n", ENVIRON["SUPERVISOR_PROCESS_NAME"], $0); fflush() }'
+}
+exec 1> >(prefixer)
+exec 2> >(prefixer >&2)
 exec "$@"
diff --git a/docs/admin_api/media_admin_api.md b/docs/admin_api/media_admin_api.md
index 30833f3109..1177711c1e 100644
--- a/docs/admin_api/media_admin_api.md
+++ b/docs/admin_api/media_admin_api.md
@@ -46,6 +46,14 @@ to any local media, and any locally-cached copies of remote media.
 
 The media file itself (and any thumbnails) is not deleted from the server.
 
+Since Synapse 1.128.0, hashes of uploaded media are tracked. If this media
+is quarantined, Synapse will:
+
+ - Quarantine any media with a matching hash that has already been uploaded.
+ - Quarantine any future media.
+ - Quarantine any existing cached remote media.
+ - Quarantine any future remote media.
+
 ## Quarantining media by ID
 
 This API quarantines a single piece of local or remote media.
diff --git a/poetry.lock b/poetry.lock
index ed98dd9f4e..2bf511e8a6 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -34,15 +34,15 @@ tests-mypy = ["mypy (>=1.11.1) ; platform_python_implementation == \"CPython\" a
 
 [[package]]
 name = "authlib"
-version = "1.4.1"
+version = "1.5.1"
 description = "The ultimate Python library in building OAuth and OpenID Connect servers and clients."
 optional = true
 python-versions = ">=3.9"
 groups = ["main"]
-markers = "extra == \"oidc\" or extra == \"jwt\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"jwt\" or extra == \"oidc\""
 files = [
-    {file = "Authlib-1.4.1-py2.py3-none-any.whl", hash = "sha256:edc29c3f6a3e72cd9e9f45fff67fc663a2c364022eb0371c003f22d5405915c1"},
-    {file = "authlib-1.4.1.tar.gz", hash = "sha256:30ead9ea4993cdbab821dc6e01e818362f92da290c04c7f6a1940f86507a790d"},
+    {file = "authlib-1.5.1-py2.py3-none-any.whl", hash = "sha256:8408861cbd9b4ea2ff759b00b6f02fd7d81ac5a56d0b2b22c08606c6049aae11"},
+    {file = "authlib-1.5.1.tar.gz", hash = "sha256:5cbc85ecb0667312c1cdc2f9095680bb735883b123fb509fde1e65b1c5df972e"},
 ]
 
 [package.dependencies]
@@ -451,7 +451,7 @@ description = "XML bomb protection for Python stdlib modules"
 optional = true
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 groups = ["main"]
-markers = "extra == \"saml2\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"saml2\""
 files = [
     {file = "defusedxml-0.7.1-py2.py3-none-any.whl", hash = "sha256:a352e7e428770286cc899e2542b6cdaedb2b4953ff269a210103ec58f6198a61"},
     {file = "defusedxml-0.7.1.tar.gz", hash = "sha256:1bb3032db185915b62d7c6209c5a8792be6a32ab2fedacc84e01b52c51aa3e69"},
@@ -494,7 +494,7 @@ description = "XPath 1.0/2.0/3.0/3.1 parsers and selectors for ElementTree and l
 optional = true
 python-versions = ">=3.7"
 groups = ["main"]
-markers = "extra == \"saml2\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"saml2\""
 files = [
     {file = "elementpath-4.1.5-py3-none-any.whl", hash = "sha256:2ac1a2fb31eb22bbbf817f8cf6752f844513216263f0e3892c8e79782fe4bb55"},
     {file = "elementpath-4.1.5.tar.gz", hash = "sha256:c2d6dc524b29ef751ecfc416b0627668119d8812441c555d7471da41d4bacb8d"},
@@ -544,7 +544,7 @@ description = "Python wrapper for hiredis"
 optional = true
 python-versions = ">=3.8"
 groups = ["main"]
-markers = "extra == \"redis\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"redis\""
 files = [
     {file = "hiredis-3.1.0-cp310-cp310-macosx_10_15_universal2.whl", hash = "sha256:2892db9db21f0cf7cc298d09f85d3e1f6dc4c4c24463ab67f79bc7a006d51867"},
     {file = "hiredis-3.1.0-cp310-cp310-macosx_10_15_x86_64.whl", hash = "sha256:93cfa6cc25ee2ceb0be81dc61eca9995160b9e16bdb7cca4a00607d57e998918"},
@@ -890,7 +890,7 @@ description = "Jaeger Python OpenTracing Tracer implementation"
 optional = true
 python-versions = ">=3.7"
 groups = ["main"]
-markers = "extra == \"opentracing\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"opentracing\""
 files = [
     {file = "jaeger-client-4.8.0.tar.gz", hash = "sha256:3157836edab8e2c209bd2d6ae61113db36f7ee399e66b1dcbb715d87ab49bfe0"},
 ]
@@ -943,14 +943,14 @@ trio = ["async_generator ; python_version == \"3.6\"", "trio"]
 
 [[package]]
 name = "jinja2"
-version = "3.1.5"
+version = "3.1.6"
 description = "A very fast and expressive template engine."
 optional = false
 python-versions = ">=3.7"
 groups = ["main", "dev"]
 files = [
-    {file = "jinja2-3.1.5-py3-none-any.whl", hash = "sha256:aba0f4dc9ed8013c424088f68a5c226f7d6097ed89b246d7749c2ec4175c6adb"},
-    {file = "jinja2-3.1.5.tar.gz", hash = "sha256:8fefff8dc3034e27bb80d67c671eb8a9bc424c0ef4c0826edbff304cceff43bb"},
+    {file = "jinja2-3.1.6-py3-none-any.whl", hash = "sha256:85ece4451f492d0c13c5dd7c13a64681a86afae63a5f347908daf103ce6d2f67"},
+    {file = "jinja2-3.1.6.tar.gz", hash = "sha256:0137fb05990d35f1275a587e9aee6d56da821fc83491a0fb838183be43f66d6d"},
 ]
 
 [package.dependencies]
@@ -1028,7 +1028,7 @@ description = "A strictly RFC 4510 conforming LDAP V3 pure Python client library
 optional = true
 python-versions = "*"
 groups = ["main"]
-markers = "extra == \"matrix-synapse-ldap3\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"matrix-synapse-ldap3\""
 files = [
     {file = "ldap3-2.9.1-py2.py3-none-any.whl", hash = "sha256:5869596fc4948797020d3f03b7939da938778a0f9e2009f7a072ccf92b8e8d70"},
     {file = "ldap3-2.9.1.tar.gz", hash = "sha256:f3e7fc4718e3f09dda568b57100095e0ce58633bcabbed8667ce3f8fbaa4229f"},
@@ -1044,7 +1044,7 @@ description = "Powerful and Pythonic XML processing library combining libxml2/li
 optional = true
 python-versions = ">=3.6"
 groups = ["main"]
-markers = "extra == \"url-preview\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"url-preview\""
 files = [
     {file = "lxml-5.3.0-cp310-cp310-macosx_10_9_universal2.whl", hash = "sha256:dd36439be765e2dde7660212b5275641edbc813e7b24668831a5c8ac91180656"},
     {file = "lxml-5.3.0-cp310-cp310-macosx_10_9_x86_64.whl", hash = "sha256:ae5fe5c4b525aa82b8076c1a59d642c17b6e8739ecf852522c6321852178119d"},
@@ -1330,7 +1330,7 @@ description = "An LDAP3 auth provider for Synapse"
 optional = true
 python-versions = ">=3.7"
 groups = ["main"]
-markers = "extra == \"matrix-synapse-ldap3\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"matrix-synapse-ldap3\""
 files = [
     {file = "matrix-synapse-ldap3-0.3.0.tar.gz", hash = "sha256:8bb6517173164d4b9cc44f49de411d8cebdb2e705d5dd1ea1f38733c4a009e1d"},
     {file = "matrix_synapse_ldap3-0.3.0-py3-none-any.whl", hash = "sha256:8b4d701f8702551e98cc1d8c20dbed532de5613584c08d0df22de376ba99159d"},
@@ -1551,7 +1551,7 @@ description = "OpenTracing API for Python. See documentation at http://opentraci
 optional = true
 python-versions = "*"
 groups = ["main"]
-markers = "extra == \"opentracing\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"opentracing\""
 files = [
     {file = "opentracing-2.4.0.tar.gz", hash = "sha256:a173117e6ef580d55874734d1fa7ecb6f3655160b8b8974a2a1e98e5ec9c840d"},
 ]
@@ -1588,14 +1588,14 @@ dev = ["jinja2"]
 
 [[package]]
 name = "phonenumbers"
-version = "8.13.50"
+version = "9.0.2"
 description = "Python version of Google's common library for parsing, formatting, storing and validating international phone numbers."
 optional = false
 python-versions = "*"
 groups = ["main"]
 files = [
-    {file = "phonenumbers-8.13.50-py2.py3-none-any.whl", hash = "sha256:bb95dbc0d9979c51f7ad94bcd780784938958861fbb4b75a2fe39ccd3d58954a"},
-    {file = "phonenumbers-8.13.50.tar.gz", hash = "sha256:e05ac6fb7b98c6d719a87ea895b9fc153673b4a51f455ec9afaf557ef4629da6"},
+    {file = "phonenumbers-9.0.2-py2.py3-none-any.whl", hash = "sha256:dbcec6bdfdf3973f60b81dc0fcac3f7b1638f877ac42da4d7b46724ed413e2b9"},
+    {file = "phonenumbers-9.0.2.tar.gz", hash = "sha256:f590ee2b729bdd9873ca2d52989466add14c9953b48805c0aeb408348d4d6224"},
 ]
 
 [[package]]
@@ -1709,7 +1709,7 @@ description = "psycopg2 - Python-PostgreSQL Database Adapter"
 optional = true
 python-versions = ">=3.8"
 groups = ["main"]
-markers = "extra == \"postgres\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"postgres\""
 files = [
     {file = "psycopg2-2.9.10-cp310-cp310-win32.whl", hash = "sha256:5df2b672140f95adb453af93a7d669d7a7bf0a56bcd26f1502329166f4a61716"},
     {file = "psycopg2-2.9.10-cp310-cp310-win_amd64.whl", hash = "sha256:c6f7b8561225f9e711a9c47087388a97fdc948211c10a4bccbf0ba68ab7b3b5a"},
@@ -1730,7 +1730,7 @@ description = ".. image:: https://travis-ci.org/chtd/psycopg2cffi.svg?branch=mas
 optional = true
 python-versions = "*"
 groups = ["main"]
-markers = "platform_python_implementation == \"PyPy\" and (extra == \"postgres\" or extra == \"all\")"
+markers = "platform_python_implementation == \"PyPy\" and (extra == \"all\" or extra == \"postgres\")"
 files = [
     {file = "psycopg2cffi-2.9.0.tar.gz", hash = "sha256:7e272edcd837de3a1d12b62185eb85c45a19feda9e62fa1b120c54f9e8d35c52"},
 ]
@@ -1746,7 +1746,7 @@ description = "A Simple library to enable psycopg2 compatability"
 optional = true
 python-versions = "*"
 groups = ["main"]
-markers = "platform_python_implementation == \"PyPy\" and (extra == \"postgres\" or extra == \"all\")"
+markers = "platform_python_implementation == \"PyPy\" and (extra == \"all\" or extra == \"postgres\")"
 files = [
     {file = "psycopg2cffi-compat-1.1.tar.gz", hash = "sha256:d25e921748475522b33d13420aad5c2831c743227dc1f1f2585e0fdb5c914e05"},
 ]
@@ -1929,14 +1929,14 @@ typing-extensions = ">=4.6.0,<4.7.0 || >4.7.0"
 
 [[package]]
 name = "pygithub"
-version = "2.5.0"
+version = "2.6.1"
 description = "Use the full Github API v3"
 optional = false
 python-versions = ">=3.8"
 groups = ["dev"]
 files = [
-    {file = "PyGithub-2.5.0-py3-none-any.whl", hash = "sha256:b0b635999a658ab8e08720bdd3318893ff20e2275f6446fcf35bf3f44f2c0fd2"},
-    {file = "pygithub-2.5.0.tar.gz", hash = "sha256:e1613ac508a9be710920d26eb18b1905ebd9926aa49398e88151c1b526aad3cf"},
+    {file = "PyGithub-2.6.1-py3-none-any.whl", hash = "sha256:6f2fa6d076ccae475f9fc392cc6cdbd54db985d4f69b8833a28397de75ed6ca3"},
+    {file = "pygithub-2.6.1.tar.gz", hash = "sha256:b5c035392991cca63959e9453286b41b54d83bf2de2daa7d7ff7e4312cebf3bf"},
 ]
 
 [package.dependencies]
@@ -1969,7 +1969,7 @@ description = "Python extension wrapping the ICU C++ API"
 optional = true
 python-versions = "*"
 groups = ["main"]
-markers = "extra == \"user-search\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"user-search\""
 files = [
     {file = "PyICU-2.14.tar.gz", hash = "sha256:acc7eb92bd5c554ed577249c6978450a4feda0aa6f01470152b3a7b382a02132"},
 ]
@@ -2018,7 +2018,7 @@ description = "A development tool to measure, monitor and analyze the memory beh
 optional = true
 python-versions = ">=3.6"
 groups = ["main"]
-markers = "extra == \"cache-memory\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"cache-memory\""
 files = [
     {file = "Pympler-1.0.1-py3-none-any.whl", hash = "sha256:d260dda9ae781e1eab6ea15bacb84015849833ba5555f141d2d9b7b7473b307d"},
     {file = "Pympler-1.0.1.tar.gz", hash = "sha256:993f1a3599ca3f4fcd7160c7545ad06310c9e12f70174ae7ae8d4e25f6c5d3fa"},
@@ -2077,7 +2077,7 @@ description = "Python implementation of SAML Version 2 Standard"
 optional = true
 python-versions = ">=3.9,<4.0"
 groups = ["main"]
-markers = "extra == \"saml2\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"saml2\""
 files = [
     {file = "pysaml2-7.5.0-py3-none-any.whl", hash = "sha256:bc6627cc344476a83c757f440a73fda1369f13b6fda1b4e16bca63ffbabb5318"},
     {file = "pysaml2-7.5.0.tar.gz", hash = "sha256:f36871d4e5ee857c6b85532e942550d2cf90ea4ee943d75eb681044bbc4f54f7"},
@@ -2102,7 +2102,7 @@ description = "Extensions to the standard Python datetime module"
 optional = true
 python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,>=2.7"
 groups = ["main"]
-markers = "extra == \"saml2\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"saml2\""
 files = [
     {file = "python-dateutil-2.8.2.tar.gz", hash = "sha256:0123cacc1627ae19ddf3c27a5de5bd67ee4586fbdd6440d9748f8abb483d3e86"},
     {file = "python_dateutil-2.8.2-py2.py3-none-any.whl", hash = "sha256:961d03dc3453ebbc59dbdea9e4e11c5651520a876d0f4db161e8674aae935da9"},
@@ -2130,7 +2130,7 @@ description = "World timezone definitions, modern and historical"
 optional = true
 python-versions = "*"
 groups = ["main"]
-markers = "extra == \"saml2\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"saml2\""
 files = [
     {file = "pytz-2022.7.1-py2.py3-none-any.whl", hash = "sha256:78f4f37d8198e0627c5f1143240bb0206b8691d8d7ac6d78fee88b78733f8c4a"},
     {file = "pytz-2022.7.1.tar.gz", hash = "sha256:01a0681c4b9684a28304615eba55d1ab31ae00bf68ec157ec3708a8182dbbcd0"},
@@ -2494,7 +2494,7 @@ description = "Python client for Sentry (https://sentry.io)"
 optional = true
 python-versions = ">=3.6"
 groups = ["main"]
-markers = "extra == \"sentry\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"sentry\""
 files = [
     {file = "sentry_sdk-2.22.0-py2.py3-none-any.whl", hash = "sha256:3d791d631a6c97aad4da7074081a57073126c69487560c6f8bffcf586461de66"},
     {file = "sentry_sdk-2.22.0.tar.gz", hash = "sha256:b4bf43bb38f547c84b2eadcefbe389b36ef75f3f38253d7a74d6b928c07ae944"},
@@ -2678,7 +2678,7 @@ description = "Tornado IOLoop Backed Concurrent Futures"
 optional = true
 python-versions = "*"
 groups = ["main"]
-markers = "extra == \"opentracing\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"opentracing\""
 files = [
     {file = "threadloop-1.0.2-py2-none-any.whl", hash = "sha256:5c90dbefab6ffbdba26afb4829d2a9df8275d13ac7dc58dccb0e279992679599"},
     {file = "threadloop-1.0.2.tar.gz", hash = "sha256:8b180aac31013de13c2ad5c834819771992d350267bddb854613ae77ef571944"},
@@ -2694,7 +2694,7 @@ description = "Python bindings for the Apache Thrift RPC system"
 optional = true
 python-versions = "*"
 groups = ["main"]
-markers = "extra == \"opentracing\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"opentracing\""
 files = [
     {file = "thrift-0.16.0.tar.gz", hash = "sha256:2b5b6488fcded21f9d312aa23c9ff6a0195d0f6ae26ddbd5ad9e3e25dfc14408"},
 ]
@@ -2756,7 +2756,7 @@ description = "Tornado is a Python web framework and asynchronous networking lib
 optional = true
 python-versions = ">=3.8"
 groups = ["main"]
-markers = "extra == \"opentracing\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"opentracing\""
 files = [
     {file = "tornado-6.4.2-cp38-abi3-macosx_10_9_universal2.whl", hash = "sha256:e828cce1123e9e44ae2a50a9de3055497ab1d0aeb440c5ac23064d9e44880da1"},
     {file = "tornado-6.4.2-cp38-abi3-macosx_10_9_x86_64.whl", hash = "sha256:072ce12ada169c5b00b7d92a99ba089447ccc993ea2143c9ede887e0937aa803"},
@@ -2890,7 +2890,7 @@ description = "non-blocking redis client for python"
 optional = true
 python-versions = "*"
 groups = ["main"]
-markers = "extra == \"redis\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"redis\""
 files = [
     {file = "txredisapi-1.4.10-py3-none-any.whl", hash = "sha256:0a6ea77f27f8cf092f907654f08302a97b48fa35f24e0ad99dfb74115f018161"},
     {file = "txredisapi-1.4.10.tar.gz", hash = "sha256:7609a6af6ff4619a3189c0adfb86aeda789afba69eb59fc1e19ac0199e725395"},
@@ -3218,7 +3218,7 @@ description = "An XML Schema validator and decoder"
 optional = true
 python-versions = ">=3.7"
 groups = ["main"]
-markers = "extra == \"saml2\" or extra == \"all\""
+markers = "extra == \"all\" or extra == \"saml2\""
 files = [
     {file = "xmlschema-2.4.0-py3-none-any.whl", hash = "sha256:dc87be0caaa61f42649899189aab2fd8e0d567f2cf548433ba7b79278d231a4a"},
     {file = "xmlschema-2.4.0.tar.gz", hash = "sha256:d74cd0c10866ac609e1ef94a5a69b018ad16e39077bc6393408b40c6babee793"},
diff --git a/pyproject.toml b/pyproject.toml
index e91a75445c..da469aab2c 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -97,7 +97,7 @@ module-name = "synapse.synapse_rust"
 
 [tool.poetry]
 name = "matrix-synapse"
-version = "1.127.1"
+version = "1.128.0rc1"
 description = "Homeserver for the Matrix decentralised comms protocol"
 authors = ["Matrix.org Team and Contributors <packages@matrix.org>"]
 license = "AGPL-3.0-or-later"
diff --git a/synapse/api/auth/msc3861_delegated.py b/synapse/api/auth/msc3861_delegated.py
index e6bf271a1f..74e526123f 100644
--- a/synapse/api/auth/msc3861_delegated.py
+++ b/synapse/api/auth/msc3861_delegated.py
@@ -19,6 +19,7 @@
 #
 #
 import logging
+from dataclasses import dataclass
 from typing import TYPE_CHECKING, Any, Callable, Dict, List, Optional
 from urllib.parse import urlencode
 
@@ -47,6 +48,7 @@ from synapse.logging.context import make_deferred_yieldable
 from synapse.types import Requester, UserID, create_requester
 from synapse.util import json_decoder
 from synapse.util.caches.cached_call import RetryOnExceptionCachedCall
+from synapse.util.caches.response_cache import ResponseCache
 
 if TYPE_CHECKING:
     from synapse.rest.admin.experimental_features import ExperimentalFeature
@@ -76,6 +78,61 @@ def scope_to_list(scope: str) -> List[str]:
     return scope.strip().split(" ")
 
 
+@dataclass
+class IntrospectionResult:
+    _inner: IntrospectionToken
+
+    # when we retrieved this token,
+    # in milliseconds since the Unix epoch
+    retrieved_at_ms: int
+
+    def is_active(self, now_ms: int) -> bool:
+        if not self._inner.get("active"):
+            return False
+
+        expires_in = self._inner.get("expires_in")
+        if expires_in is None:
+            return True
+        if not isinstance(expires_in, int):
+            raise InvalidClientTokenError("token `expires_in` is not an int")
+
+        absolute_expiry_ms = expires_in * 1000 + self.retrieved_at_ms
+        return now_ms < absolute_expiry_ms
+
+    def get_scope_list(self) -> List[str]:
+        value = self._inner.get("scope")
+        if not isinstance(value, str):
+            return []
+        return scope_to_list(value)
+
+    def get_sub(self) -> Optional[str]:
+        value = self._inner.get("sub")
+        if not isinstance(value, str):
+            return None
+        return value
+
+    def get_username(self) -> Optional[str]:
+        value = self._inner.get("username")
+        if not isinstance(value, str):
+            return None
+        return value
+
+    def get_name(self) -> Optional[str]:
+        value = self._inner.get("name")
+        if not isinstance(value, str):
+            return None
+        return value
+
+    def get_device_id(self) -> Optional[str]:
+        value = self._inner.get("device_id")
+        if value is not None and not isinstance(value, str):
+            raise AuthError(
+                500,
+                "Invalid device ID in introspection result",
+            )
+        return value
+
+
 class PrivateKeyJWTWithKid(PrivateKeyJWT):  # type: ignore[misc]
     """An implementation of the private_key_jwt client auth method that includes a kid header.
 
@@ -121,6 +178,31 @@ class MSC3861DelegatedAuth(BaseAuth):
         self._hostname = hs.hostname
         self._admin_token: Callable[[], Optional[str]] = self._config.admin_token
 
+        # # Token Introspection Cache
+        # This remembers what users/devices are represented by which access tokens,
+        # in order to reduce overall system load:
+        # - on Synapse (as requests are relatively expensive)
+        # - on the network
+        # - on MAS
+        #
+        # Since there is no invalidation mechanism currently,
+        # the entries expire after 2 minutes.
+        # This does mean tokens can be treated as valid by Synapse
+        # for longer than reality.
+        #
+        # Ideally, tokens should logically be invalidated in the following circumstances:
+        # - If a session logout happens.
+        #   In this case, MAS will delete the device within Synapse
+        #   anyway and this is good enough as an invalidation.
+        # - If the client refreshes their token in MAS.
+        #   In this case, the device still exists and it's not the end of the world for
+        #   the old access token to continue working for a short time.
+        self._introspection_cache: ResponseCache[str] = ResponseCache(
+            self._clock,
+            "token_introspection",
+            timeout_ms=120_000,
+        )
+
         self._issuer_metadata = RetryOnExceptionCachedCall[OpenIDProviderMetadata](
             self._load_metadata
         )
@@ -193,7 +275,7 @@ class MSC3861DelegatedAuth(BaseAuth):
         metadata = await self._issuer_metadata.get()
         return metadata.get("introspection_endpoint")
 
-    async def _introspect_token(self, token: str) -> IntrospectionToken:
+    async def _introspect_token(self, token: str) -> IntrospectionResult:
         """
         Send a token to the introspection endpoint and returns the introspection response
 
@@ -266,7 +348,9 @@ class MSC3861DelegatedAuth(BaseAuth):
                 "The introspection endpoint returned an invalid JSON response."
             )
 
-        return IntrospectionToken(**resp)
+        return IntrospectionResult(
+            IntrospectionToken(**resp), retrieved_at_ms=self._clock.time_msec()
+        )
 
     async def is_server_admin(self, requester: Requester) -> bool:
         return "urn:synapse:admin:*" in requester.scope
@@ -344,7 +428,9 @@ class MSC3861DelegatedAuth(BaseAuth):
             )
 
         try:
-            introspection_result = await self._introspect_token(token)
+            introspection_result = await self._introspection_cache.wrap(
+                token, self._introspect_token, token
+            )
         except Exception:
             logger.exception("Failed to introspect token")
             raise SynapseError(503, "Unable to introspect the access token")
@@ -353,11 +439,11 @@ class MSC3861DelegatedAuth(BaseAuth):
 
         # TODO: introspection verification should be more extensive, especially:
         #   - verify the audience
-        if not introspection_result.get("active"):
+        if not introspection_result.is_active(self._clock.time_msec()):
             raise InvalidClientTokenError("Token is not active")
 
         # Let's look at the scope
-        scope: List[str] = scope_to_list(introspection_result.get("scope", ""))
+        scope: List[str] = introspection_result.get_scope_list()
 
         # Determine type of user based on presence of particular scopes
         has_user_scope = SCOPE_MATRIX_API in scope
@@ -367,7 +453,7 @@ class MSC3861DelegatedAuth(BaseAuth):
             raise InvalidClientTokenError("No scope in token granting user rights")
 
         # Match via the sub claim
-        sub: Optional[str] = introspection_result.get("sub")
+        sub: Optional[str] = introspection_result.get_sub()
         if sub is None:
             raise InvalidClientTokenError(
                 "Invalid sub claim in the introspection result"
@@ -381,7 +467,7 @@ class MSC3861DelegatedAuth(BaseAuth):
             # or the external_id was never recorded
 
             # TODO: claim mapping should be configurable
-            username: Optional[str] = introspection_result.get("username")
+            username: Optional[str] = introspection_result.get_username()
             if username is None or not isinstance(username, str):
                 raise AuthError(
                     500,
@@ -399,7 +485,7 @@ class MSC3861DelegatedAuth(BaseAuth):
 
                 # TODO: claim mapping should be configurable
                 # If present, use the name claim as the displayname
-                name: Optional[str] = introspection_result.get("name")
+                name: Optional[str] = introspection_result.get_name()
 
                 await self.store.register_user(
                     user_id=user_id.to_string(), create_profile_with_displayname=name
@@ -414,15 +500,8 @@ class MSC3861DelegatedAuth(BaseAuth):
 
         # MAS 0.15+ will give us the device ID as an explicit value for compatibility sessions
         # If present, we get it from here, if not we get it in thee scope
-        device_id = introspection_result.get("device_id")
-        if device_id is not None:
-            # We got the device ID explicitly, just sanity check that it's a string
-            if not isinstance(device_id, str):
-                raise AuthError(
-                    500,
-                    "Invalid device ID in introspection result",
-                )
-        else:
+        device_id = introspection_result.get_device_id()
+        if device_id is None:
             # Find device_ids in scope
             # We only allow a single device_id in the scope, so we find them all in the
             # scope list, and raise if there are more than one. The OIDC server should be
diff --git a/synapse/storage/databases/main/media_repository.py b/synapse/storage/databases/main/media_repository.py
index 8a5ba44922..04866524e3 100644
--- a/synapse/storage/databases/main/media_repository.py
+++ b/synapse/storage/databases/main/media_repository.py
@@ -999,6 +999,15 @@ class MediaRepositoryStore(MediaRepositoryBackgroundUpdateStore):
             None if the media_id doesn't exist.
         """
 
+        # If we don't have the index yet, performance tanks, so we return False.
+        # In the background updates, remote_media_cache_sha256_idx is created
+        # after local_media_repository_sha256_idx, which is why we only need to
+        # check for the completion of the former.
+        if not await self.db_pool.updates.has_completed_background_update(
+            "remote_media_cache_sha256_idx"
+        ):
+            return False
+
         def get_matching_media_txn(
             txn: LoggingTransaction, table: str, sha256: str
         ) -> bool:
diff --git a/synapse/storage/databases/state/store.py b/synapse/storage/databases/state/store.py
index 90d7beb92f..c1a66dcba0 100644
--- a/synapse/storage/databases/state/store.py
+++ b/synapse/storage/databases/state/store.py
@@ -48,6 +48,7 @@ from synapse.storage.database import (
     LoggingTransaction,
 )
 from synapse.storage.databases.state.bg_updates import StateBackgroundUpdateStore
+from synapse.storage.engines import PostgresEngine
 from synapse.storage.types import Cursor
 from synapse.storage.util.sequence import build_sequence_generator
 from synapse.types import MutableStateMap, StateKey, StateMap
@@ -914,6 +915,12 @@ class StateGroupDataStore(StateBackgroundUpdateStore, SQLBaseStore):
     ) -> None:
         # Delete all edges that reference a state group linked to room_id
         logger.info("[purge] removing %s from state_group_edges", room_id)
+
+        if isinstance(self.database_engine, PostgresEngine):
+            # Disable statement timeouts for this transaction; purging rooms can
+            # take a while!
+            txn.execute("SET LOCAL statement_timeout = 0")
+
         txn.execute(
             """
             DELETE FROM state_group_edges AS sge WHERE sge.state_group IN (
diff --git a/synapse/storage/schema/main/delta/91/01_media_hash.sql b/synapse/storage/schema/main/delta/91/01_media_hash.sql
index 2dbd2c7df7..34a372f1ed 100644
--- a/synapse/storage/schema/main/delta/91/01_media_hash.sql
+++ b/synapse/storage/schema/main/delta/91/01_media_hash.sql
@@ -16,6 +16,13 @@ ALTER TABLE local_media_repository ADD COLUMN sha256 TEXT;
 ALTER TABLE remote_media_cache ADD COLUMN sha256 TEXT;
 
 -- Add a background updates to handle creating the new index.
-INSERT INTO background_updates (ordering, update_name, progress_json) VALUES
-    (9101, 'local_media_repository_sha256_idx', '{}'),
-    (9101, 'remote_media_cache_sha256_idx', '{}');
\ No newline at end of file
+--
+-- Note that the ordering of the update is not following the usual scheme. This
+-- is because when upgrading from Synapse 1.127, this index is fairly important
+-- to have up quickly, so that it doesn't tank performance, which is why it is
+-- scheduled before other background updates in the 1.127 -> 1.128 upgrade
+INSERT INTO
+  background_updates (ordering, update_name, progress_json)
+VALUES
+  (8890, 'local_media_repository_sha256_idx', '{}'),
+  (8891, 'remote_media_cache_sha256_idx', '{}');
diff --git a/tests/handlers/test_oauth_delegation.py b/tests/handlers/test_oauth_delegation.py
index 5f8c25557a..034a1594d9 100644
--- a/tests/handlers/test_oauth_delegation.py
+++ b/tests/handlers/test_oauth_delegation.py
@@ -539,6 +539,44 @@ class MSC3861OAuthDelegation(HomeserverTestCase):
         error = self.get_failure(self.auth.get_user_by_req(request), SynapseError)
         self.assertEqual(error.value.code, 503)
 
+    def test_cached_expired_introspection(self) -> None:
+        """The handler should raise an error if the introspection response gives
+        an expiry time, the introspection response is cached and then the entry is
+        re-requested after it has expired."""
+
+        self.http_client.request = introspection_mock = AsyncMock(
+            return_value=FakeResponse.json(
+                code=200,
+                payload={
+                    "active": True,
+                    "sub": SUBJECT,
+                    "scope": " ".join(
+                        [
+                            MATRIX_USER_SCOPE,
+                            f"{MATRIX_DEVICE_SCOPE_PREFIX}AABBCC",
+                        ]
+                    ),
+                    "username": USERNAME,
+                    "expires_in": 60,
+                },
+            )
+        )
+        request = Mock(args={})
+        request.args[b"access_token"] = [b"mockAccessToken"]
+        request.requestHeaders.getRawHeaders = mock_getRawHeaders()
+
+        # The first CS-API request causes a successful introspection
+        self.get_success(self.auth.get_user_by_req(request))
+        self.assertEqual(introspection_mock.call_count, 1)
+
+        # Sleep for 60 seconds so the token expires.
+        self.reactor.advance(60.0)
+
+        # Now the CS-API request fails because the token expired
+        self.get_failure(self.auth.get_user_by_req(request), InvalidClientTokenError)
+        # Ensure another introspection request was not sent
+        self.assertEqual(introspection_mock.call_count, 1)
+
     def make_device_keys(self, user_id: str, device_id: str) -> JsonDict:
         # We only generate a master key to simplify the test.
         master_signing_key = generate_signing_key(device_id)