- Add experimental support for sending to-device messages to application services, as specified by [MSC2409](https://github.com/matrix-org/matrix-doc/pull/2409). Disabled by default. ([\#11215](https://github.com/matrix-org/synapse/issues/11215), [\#11966](https://github.com/matrix-org/synapse/issues/11966))
- Add experimental support for sending to-device messages to application services, as specified by [MSC2409](https://github.com/matrix-org/matrix-doc/pull/2409). ([\#11215](https://github.com/matrix-org/synapse/issues/11215), [\#11966](https://github.com/matrix-org/synapse/issues/11966))
- Remove account data (including client config, push rules and ignored users) upon user deactivation. ([\#11655](https://github.com/matrix-org/synapse/issues/11655))
- Experimental support for [MSC3666](https://github.com/matrix-org/matrix-doc/pull/3666): including bundled aggregations in server side search results. ([\#11837](https://github.com/matrix-org/synapse/issues/11837))
- Enable cache time-based expiry by default. The `expiry_time` config flag has been superseded by `expire_caches` and `cache_entry_ttl`. ([\#11849](https://github.com/matrix-org/synapse/issues/11849))
- Add a callback to allow modules to allow or forbid a 3PID (email address, phone number) from being associated to a local account. ([\#11854](https://github.com/matrix-org/synapse/issues/11854))
- Stabilize support for [MSC3231](https://github.com/matrix-org/matrix-doc/pull/3231). Clients should switch to the stable identifier and endpoint. ([\#11867](https://github.com/matrix-org/synapse/issues/11867))
- Stabilize support and remove unstable endpoints for [MSC3231](https://github.com/matrix-org/matrix-doc/pull/3231). Clients must switch to the stable identifier and endpoint. See the [upgrade notes](https://matrix-org.github.io/synapse/develop/upgrade#stablisation-of-msc3231) for more information. ([\#11867](https://github.com/matrix-org/synapse/issues/11867))
- Allow modules to retrieve the current instance's server name and worker name. ([\#11868](https://github.com/matrix-org/synapse/issues/11868))
- Use a dedicated configurable rate limiter for 3PID invites. ([\#11892](https://github.com/matrix-org/synapse/issues/11892))
- Support the stable API endpoint for [MSC3283](https://github.com/matrix-org/matrix-doc/pull/3283): new settings in `/capabilities` endpoint. ([\#11933](https://github.com/matrix-org/synapse/issues/11933), [\#11989](https://github.com/matrix-org/synapse/issues/11989))
...
...
@@ -21,7 +21,7 @@ Bugfixes
--------
- Fix [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) historical messages backfilling in random order on remote homeservers. ([\#11114](https://github.com/matrix-org/synapse/issues/11114))
- Fix a bug introduced in Synapse 1.51.0rc1 where incoming federation transactions containing at least one EDU would be dropped if debug logging was enabled for `synapse.8631_debug`. ([\#11890](https://github.com/matrix-org/synapse/issues/11890))
- Fix a bug introduced in Synapse 1.51.0 where incoming federation transactions containing at least one EDU would be dropped if debug logging was enabled for `synapse.8631_debug`. ([\#11890](https://github.com/matrix-org/synapse/issues/11890))
- Fix a long-standing bug where some unknown endpoints would return HTML error pages instead of JSON `M_UNRECOGNIZED` errors. ([\#11930](https://github.com/matrix-org/synapse/issues/11930))
- Implement an allow list of content types for which we will attempt to preview a URL. This prevents Synapse from making useless longer-lived connections to streaming media servers. ([\#11936](https://github.com/matrix-org/synapse/issues/11936))
- Fix a long-standing bug where pagination tokens from `/sync` and `/messages` could not be provided to the `/relations` API. ([\#11952](https://github.com/matrix-org/synapse/issues/11952))
...
...
@@ -51,7 +51,7 @@ Deprecations and Removals
Internal Changes
----------------
- Enhance user registration test helpers to make them more useful for tests involving Application Services and devices. ([\#11615](https://github.com/matrix-org/synapse/issues/11615), [\#11616](https://github.com/matrix-org/synapse/issues/11616))
- Enhance user registration test helpers to make them more useful for tests involving application services and devices. ([\#11615](https://github.com/matrix-org/synapse/issues/11615), [\#11616](https://github.com/matrix-org/synapse/issues/11616))
- Improve performance when fetching bundled aggregations for multiple events. ([\#11660](https://github.com/matrix-org/synapse/issues/11660), [\#11752](https://github.com/matrix-org/synapse/issues/11752))
- Fix type errors introduced by new annotations in the Prometheus Client library. ([\#11832](https://github.com/matrix-org/synapse/issues/11832))
- Add missing type hints to replication code. ([\#11856](https://github.com/matrix-org/synapse/issues/11856), [\#11938](https://github.com/matrix-org/synapse/issues/11938))
...
...
@@ -68,12 +68,12 @@ Internal Changes
- Various refactors to the application service notifier code. ([\#11911](https://github.com/matrix-org/synapse/issues/11911), [\#11912](https://github.com/matrix-org/synapse/issues/11912))
- Tests: replace mocked `Authenticator` with the real thing. ([\#11913](https://github.com/matrix-org/synapse/issues/11913))
- Various refactors to the typing notifications code. ([\#11914](https://github.com/matrix-org/synapse/issues/11914))
- Use the proper type for the Content-Length header in the `UploadResource`. ([\#11927](https://github.com/matrix-org/synapse/issues/11927))
- Use the proper type for the `Content-Length` header in the `UploadResource`. ([\#11927](https://github.com/matrix-org/synapse/issues/11927))
- Remove an unnecessary ignoring of type hints due to fixes in upstream packages. ([\#11939](https://github.com/matrix-org/synapse/issues/11939))
- Add missing type hints. ([\#11953](https://github.com/matrix-org/synapse/issues/11953))
- Fix an import cycle in `synapse.event_auth`. ([\#11965](https://github.com/matrix-org/synapse/issues/11965))
- Unpin frozendict but exclude the known bad version 2.1.2. ([\#11969](https://github.com/matrix-org/synapse/issues/11969))
- Prepare for rename of default complement branch. ([\#11971](https://github.com/matrix-org/synapse/issues/11971))
- Unpin `frozendict` but exclude the known bad version 2.1.2. ([\#11969](https://github.com/matrix-org/synapse/issues/11969))
- Prepare for rename of default Complement branch. ([\#11971](https://github.com/matrix-org/synapse/issues/11971))
- Fetch Synapse's version using a helper from `matrix-common`. ([\#11979](https://github.com/matrix-org/synapse/issues/11979))
