CHANGES.md

--------

- Allow room creators to send historical events specified by [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) in existing room versions. ([\#10566](https://github.com/matrix-org/synapse/issues/10566))
- Add config option to use non-default manhole password and keys. ([\#10643](https://github.com/matrix-org/synapse/issues/10643))
- Skip final GC at shutdown to improve restart performance. ([\#10712](https://github.com/matrix-org/synapse/issues/10712))
- Allow configuration of the oEmbed URLs used for URL previews. ([\#10714](https://github.com/matrix-org/synapse/issues/10714), [\#10759](https://github.com/matrix-org/synapse/issues/10759))
- Prefer [room version 9](https://github.com/matrix-org/matrix-doc/pull/3375) for restricted rooms per the [room version capabilities](https://github.com/matrix-org/matrix-doc/pull/3244) API. ([\#10772](https://github.com/matrix-org/synapse/issues/10772))


Bugfixes
--------

- Fix a long-standing bug where room avatars were not included in email notifications. ([\#10658](https://github.com/matrix-org/synapse/issues/10658))
- Fix a bug where the ordering algorithm was skipping the `origin_server_ts` step in the spaces summary resulting in unstable room orderings. ([\#10730](https://github.com/matrix-org/synapse/issues/10730))
- Fix edge case when persisting events into a room where there are multiple events we previously hadn't calculated auth chains for (and hadn't marked as needing to be calculated). ([\#10743](https://github.com/matrix-org/synapse/issues/10743))
- Fix a bug which prevented calls to `/createRoom` that included the `room_alias_name` parameter from being handled by worker processes. ([\#10757](https://github.com/matrix-org/synapse/issues/10757))
- Fix a bug which prevented user registration via SSO to require consent tracking for SSO mapping providers that don't prompt for Matrix ID selection. Contributed by @AndrewFerr. ([\#10733](https://github.com/matrix-org/synapse/issues/10733))
- Only return the stripped state events for the `m.space.child` events in a room for the spaces summary from [MSC2946](https://github.com/matrix-org/matrix-doc/pull/2946). ([\#10760](https://github.com/matrix-org/synapse/issues/10760))
- Properly handle room upgrades of spaces. ([\#10774](https://github.com/matrix-org/synapse/issues/10774))
- Fix a bug which generated invalid homeserver config when the `frontend_proxy` worker type was passed to the Synapse Worker-based Complement image. ([\#10783](https://github.com/matrix-org/synapse/issues/10783))


Improved Documentation
----------------------

- Minor fix to the `media_repository` developer documentation. Contributed by @cuttingedge1109. ([\#10556](https://github.com/matrix-org/synapse/issues/10556))
- Update the documentation to note that the `/spaces` and `/hierarchy` endpoints can be routed to workers. ([\#10648](https://github.com/matrix-org/synapse/issues/10648))
- Clarify admin API documentation on undoing room deletions. ([\#10735](https://github.com/matrix-org/synapse/issues/10735))
- Split up the modules documentation and add examples for module developers. ([\#10758](https://github.com/matrix-org/synapse/issues/10758))
- Correct 2 typographical errors in the [Log Contexts documentation](https://matrix-org.github.io/synapse/latest/log_contexts.html). ([\#10795](https://github.com/matrix-org/synapse/issues/10795))
- Fix a wording mistake in the sample configuration. Contributed by @bramvdnheuvel:nltrix.net. ([\#10804](https://github.com/matrix-org/synapse/issues/10804))


Deprecations and Removals
-------------------------

- Remove the [unstable MSC2858 API](https://github.com/matrix-org/matrix-doc/blob/master/proposals/2858-Multiple-SSO-Identity-Providers.md#unstable-prefix), including the undocumented `experimental.msc2858_enabled` config option. The unstable API has been deprecated since Synapse 1.35. Client authors should update their clients to use the stable API introduced in Synapse 1.30 if they have not already done so. ([\#10693](https://github.com/matrix-org/synapse/issues/10693))


Internal Changes
----------------

- Add OpenTracing logging to help debug stuck messages (as described by issue [#9424](https://github.com/matrix-org/synapse/issues/9424)). ([\#10704](https://github.com/matrix-org/synapse/issues/10704))
- Add type annotations to the `synapse.util` package. ([\#10601](https://github.com/matrix-org/synapse/issues/10601))
- Ensure `rooms.creator` field is always populated for easy lookup in [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) usage later. ([\#10697](https://github.com/matrix-org/synapse/issues/10697))
- Add missing type hints to REST servlets. ([\#10707](https://github.com/matrix-org/synapse/issues/10707), [\#10728](https://github.com/matrix-org/synapse/issues/10728), [\#10736](https://github.com/matrix-org/synapse/issues/10736))
- Do not include rooms with unknown room versions in the spaces summary results. ([\#10727](https://github.com/matrix-org/synapse/issues/10727))
- Additional error checking for the `preset` field when creating a room. ([\#10738](https://github.com/matrix-org/synapse/issues/10738))
- Clean up some of the federation event authentication code for clarity. ([\#10744](https://github.com/matrix-org/synapse/issues/10744), [\#10745](https://github.com/matrix-org/synapse/issues/10745), [\#10746](https://github.com/matrix-org/synapse/issues/10746), [\#10771](https://github.com/matrix-org/synapse/issues/10771), [\#10773](https://github.com/matrix-org/synapse/issues/10773), [\#10781](https://github.com/matrix-org/synapse/issues/10781))
- Add an index to `presence_stream` to hopefully speed up startups a little. ([\#10748](https://github.com/matrix-org/synapse/issues/10748))
- Refactor event size checking code to simplify searching the codebase for the origins of certain error strings that are occasionally emitted. ([\#10750](https://github.com/matrix-org/synapse/issues/10750))
- Move tests relating to rooms having encryption out of the user directory tests. ([\#10752](https://github.com/matrix-org/synapse/issues/10752))
- Use `attrs` internally for the URL preview code & update documentation. ([\#10753](https://github.com/matrix-org/synapse/issues/10753))
- Minor speed ups when joining large rooms over federation. ([\#10754](https://github.com/matrix-org/synapse/issues/10754), [\#10755](https://github.com/matrix-org/synapse/issues/10755), [\#10756](https://github.com/matrix-org/synapse/issues/10756), [\#10780](https://github.com/matrix-org/synapse/issues/10780), [\#10784](https://github.com/matrix-org/synapse/issues/10784))
- Add a constant for `m.federate`. ([\#10775](https://github.com/matrix-org/synapse/issues/10775))
- Add a script to update the Debian changelog in a Docker container for systems that are not Debian-based. ([\#10778](https://github.com/matrix-org/synapse/issues/10778))
- Change the format of authenticated users in logs when a user is being puppeted by and admin user. ([\#10779](https://github.com/matrix-org/synapse/issues/10779))
- Remove fixed and flakey tests from the Sytest blacklist. ([\#10788](https://github.com/matrix-org/synapse/issues/10788))
- Improve internal details of the user directory code. ([\#10789](https://github.com/matrix-org/synapse/issues/10789))
- Use direct references to config flags. ([\#10798](https://github.com/matrix-org/synapse/issues/10798))
- Ensure the Rust reporter passes type checking with jaeger-client 4.7's type annotations. ([\#10799](https://github.com/matrix-org/synapse/issues/10799))


Synapse 1.42.0 (2021-09-07)
===========================

This version of Synapse removes deprecated room-management admin APIs, removes out-of-date email pushers, and improves error handling for fallback templates for user-interactive authentication. For more information on these points, server administrators are encouraged to read [the upgrade notes](docs/upgrade.md#upgrading-to-v1420).

No significant changes since 1.42.0rc2.


Synapse 1.42.0rc2 (2021-09-06)
==============================

Features
--------

- Support room version 9 from [MSC3375](https://github.com/matrix-org/matrix-doc/pull/3375). ([\#10747](https://github.com/matrix-org/synapse/issues/10747))


Internal Changes
----------------

- Print a warning when using one of the deprecated `template_dir` settings. ([\#10768](https://github.com/matrix-org/synapse/issues/10768))


Synapse 1.42.0rc1 (2021-09-01)
==============================

Features
--------

- Add support for [MSC3231](https://github.com/matrix-org/matrix-doc/pull/3231): Token authenticated registration. Users can be required to submit a token during registration to authenticate themselves. Contributed by Callum Brown. ([\#10142](https://github.com/matrix-org/synapse/issues/10142))
- Add support for [MSC3283](https://github.com/matrix-org/matrix-doc/pull/3283): Expose `enable_set_displayname` in capabilities. ([\#10452](https://github.com/matrix-org/synapse/issues/10452))
- Port the `PresenceRouter` module interface to the new generic interface. ([\#10524](https://github.com/matrix-org/synapse/issues/10524))
- Add pagination to the spaces summary based on updates to [MSC2946](https://github.com/matrix-org/matrix-doc/pull/2946). ([\#10613](https://github.com/matrix-org/synapse/issues/10613), [\#10725](https://github.com/matrix-org/synapse/issues/10725))


Bugfixes
--------

- Validate new `m.room.power_levels` events. Contributed by @aaronraimist. ([\#10232](https://github.com/matrix-org/synapse/issues/10232))
- Display an error on User-Interactive Authentication fallback pages when authentication fails. Contributed by Callum Brown. ([\#10561](https://github.com/matrix-org/synapse/issues/10561))
- Remove pushers when deleting an e-mail address from an account. Pushers for old unlinked emails will also be deleted. ([\#10581](https://github.com/matrix-org/synapse/issues/10581), [\#10734](https://github.com/matrix-org/synapse/issues/10734))
- Reject Client-Server `/keys/query` requests which provide `device_ids` incorrectly. ([\#10593](https://github.com/matrix-org/synapse/issues/10593))
- Rooms with unsupported room versions are no longer returned via `/sync`. ([\#10644](https://github.com/matrix-org/synapse/issues/10644))
- Enforce the maximum length for per-room display names and avatar URLs. ([\#10654](https://github.com/matrix-org/synapse/issues/10654))
- Fix a bug which caused the `synapse_user_logins_total` Prometheus metric not to be correctly initialised on restart. ([\#10677](https://github.com/matrix-org/synapse/issues/10677))
- Improve `ServerNoticeServlet` to avoid duplicate requests and add unit tests. ([\#10679](https://github.com/matrix-org/synapse/issues/10679))
- Fix long-standing issue which caused an error when a thumbnail is requested and there are multiple thumbnails with the same quality rating. ([\#10684](https://github.com/matrix-org/synapse/issues/10684))
- Fix a regression introduced in v1.41.0 which affected the performance of concurrent fetches of large sets of events, in extreme cases causing the process to hang. ([\#10703](https://github.com/matrix-org/synapse/issues/10703))
- Fix a regression introduced in Synapse 1.41 which broke email transmission on Systems using older versions of the Twisted library. ([\#10713](https://github.com/matrix-org/synapse/issues/10713))


Improved Documentation
----------------------

- Add documentation on how to connect Django with Synapse using OpenID Connect and django-oauth-toolkit. Contributed by @HugoDelval. ([\#10192](https://github.com/matrix-org/synapse/issues/10192))
- Advertise https://matrix-org.github.io/synapse documentation in the `README` and `CONTRIBUTING` files. ([\#10595](https://github.com/matrix-org/synapse/issues/10595))
- Fix some of the titles not rendering in the OpenID Connect documentation. ([\#10639](https://github.com/matrix-org/synapse/issues/10639))
- Minor clarifications to the documentation for reverse proxies. ([\#10708](https://github.com/matrix-org/synapse/issues/10708))
- Remove table of contents from the top of installation and contributing documentation pages. ([\#10711](https://github.com/matrix-org/synapse/issues/10711))


Deprecations and Removals
-------------------------

- Remove deprecated Shutdown Room and Purge Room Admin API. ([\#8830](https://github.com/matrix-org/synapse/issues/8830))


Internal Changes
----------------

- Improve type hints for the proxy agent and SRV resolver modules. Contributed by @dklimpel. ([\#10608](https://github.com/matrix-org/synapse/issues/10608))
- Clean up some of the federation event authentication code for clarity. ([\#10614](https://github.com/matrix-org/synapse/issues/10614), [\#10615](https://github.com/matrix-org/synapse/issues/10615), [\#10624](https://github.com/matrix-org/synapse/issues/10624), [\#10640](https://github.com/matrix-org/synapse/issues/10640))
- Add a comment asking developers to leave a reason when bumping the database schema version. ([\#10621](https://github.com/matrix-org/synapse/issues/10621))
- Remove not needed database updates in modify user admin API. ([\#10627](https://github.com/matrix-org/synapse/issues/10627))
- Convert room member storage tuples to `attrs` classes. ([\#10629](https://github.com/matrix-org/synapse/issues/10629), [\#10642](https://github.com/matrix-org/synapse/issues/10642))
- Use auto-attribs for the attrs classes used in sync. ([\#10630](https://github.com/matrix-org/synapse/issues/10630))
- Make `backfill` and `get_missing_events` use the same codepath. ([\#10645](https://github.com/matrix-org/synapse/issues/10645))
- Improve the performance of the `/hierarchy` API (from [MSC2946](https://github.com/matrix-org/matrix-doc/pull/2946)) by caching responses received over federation. ([\#10647](https://github.com/matrix-org/synapse/issues/10647))
- Run a nightly CI build against Twisted trunk. ([\#10651](https://github.com/matrix-org/synapse/issues/10651), [\#10672](https://github.com/matrix-org/synapse/issues/10672))
- Do not print out stack traces for network errors when fetching data over federation. ([\#10662](https://github.com/matrix-org/synapse/issues/10662))
- Simplify tests for device admin rest API. ([\#10664](https://github.com/matrix-org/synapse/issues/10664))
- Add missing type hints to REST servlets. ([\#10665](https://github.com/matrix-org/synapse/issues/10665), [\#10666](https://github.com/matrix-org/synapse/issues/10666), [\#10674](https://github.com/matrix-org/synapse/issues/10674))
- Flatten the `tests.synapse.rests` package by moving the contents of `v1` and `v2_alpha` into the parent. ([\#10667](https://github.com/matrix-org/synapse/issues/10667))
- Update `complement.sh` to rebuild the base Docker image when run with workers. ([\#10686](https://github.com/matrix-org/synapse/issues/10686))
- Split the event-processing methods in `FederationHandler` into a separate `FederationEventHandler`. ([\#10692](https://github.com/matrix-org/synapse/issues/10692))
- Remove unused `compare_digest` function. ([\#10706](https://github.com/matrix-org/synapse/issues/10706))


Synapse 1.41.1 (2021-08-31)
===========================

Due to the two security issues highlighted below, server administrators are encouraged to update Synapse. We are not aware of these vulnerabilities being exploited in the wild.

Security advisory
-----------------

The following issues are fixed in v1.41.1.

- **[GHSA-3x4c-pq33-4w3q](https://github.com/matrix-org/synapse/security/advisories/GHSA-3x4c-pq33-4w3q) / [CVE-2021-39164](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-39164): Enumerating a private room's list of members and their display names.**

  If an unauthorized user both knows the Room ID of a private room *and* that room's history visibility is set to `shared`, then they may be able to enumerate the room's members, including their display names.

  The unauthorized user must be on the same homeserver as a user who is a member of the target room.

  Fixed by [52c7a51cf](https://github.com/matrix-org/synapse/commit/52c7a51cf).

- **[GHSA-jj53-8fmw-f2w2](https://github.com/matrix-org/synapse/security/advisories/GHSA-jj53-8fmw-f2w2) / [CVE-2021-39163](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-39163): Disclosing a private room's name, avatar, topic, and number of members.**

  If an unauthorized user knows the Room ID of a private room, then its name, avatar, topic, and number of members may be disclosed through Group / Community features.

  The unauthorized user must be on the same homeserver as a user who is a member of the target room, and their homeserver must allow non-administrators to create groups (`enable_group_creation` in the Synapse configuration; off by default).

  Fixed by [cb35df940a](https://github.com/matrix-org/synapse/commit/cb35df940a), [\#10723](https://github.com/matrix-org/synapse/issues/10723).

Bugfixes
--------

- Fix a regression introduced in Synapse 1.41 which broke email transmission on systems using older versions of the Twisted library. ([\#10713](https://github.com/matrix-org/synapse/issues/10713))

Synapse 1.41.0 (2021-08-24)
===========================

This release adds support for Debian 12 (Bookworm), but **removes support for Ubuntu 20.10 (Groovy Gorilla)**, which reached End of Life last month.

Note that when using workers the `/_synapse/admin/v1/users/{userId}/media` must now be handled by media workers. See the [upgrade notes](https://matrix-org.github.io/synapse/latest/upgrade.html) for more information.


Features
--------

- Enable room capabilities ([MSC3244](https://github.com/matrix-org/matrix-doc/pull/3244)) by default and set room version 8 as the preferred room version when creating restricted rooms. ([\#10571](https://github.com/matrix-org/synapse/issues/10571))


Synapse 1.41.0rc1 (2021-08-18)
==============================

Features
--------

- Add `get_userinfo_by_id` method to ModuleApi. ([\#9581](https://github.com/matrix-org/synapse/issues/9581))
- Initial local support for [MSC3266](https://github.com/matrix-org/synapse/pull/10394), Room Summary over the unstable `/rooms/{roomIdOrAlias}/summary` API. ([\#10394](https://github.com/matrix-org/synapse/issues/10394))
- Experimental support for [MSC3288](https://github.com/matrix-org/matrix-doc/pull/3288), sending `room_type` to the identity server for 3pid invites over the `/store-invite` API. ([\#10435](https://github.com/matrix-org/synapse/issues/10435))
- Add support for sending federation requests through a proxy. Contributed by @Bubu and @dklimpel. See the [upgrade notes](https://matrix-org.github.io/synapse/latest/upgrade.html) for more information. ([\#10596](https://github.com/matrix-org/synapse/issues/10596)). ([\#10475](https://github.com/matrix-org/synapse/issues/10475))
- Add support for "marker" events which makes historical events discoverable for servers that already have all of the scrollback history (part of [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716)). ([\#10498](https://github.com/matrix-org/synapse/issues/10498))
- Add a configuration setting for the time a `/sync` response is cached for. ([\#10513](https://github.com/matrix-org/synapse/issues/10513))
- The default logging handler for new installations is now `PeriodicallyFlushingMemoryHandler`, a buffered logging handler which periodically flushes itself. ([\#10518](https://github.com/matrix-org/synapse/issues/10518))
- Add support for new redaction rules for historical events specified in [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716). ([\#10538](https://github.com/matrix-org/synapse/issues/10538))
- Add a setting to disable TLS when sending email. ([\#10546](https://github.com/matrix-org/synapse/issues/10546))
- Add pagination to the spaces summary based on updates to [MSC2946](https://github.com/matrix-org/matrix-doc/pull/2946). ([\#10549](https://github.com/matrix-org/synapse/issues/10549), [\#10560](https://github.com/matrix-org/synapse/issues/10560), [\#10569](https://github.com/matrix-org/synapse/issues/10569), [\#10574](https://github.com/matrix-org/synapse/issues/10574), [\#10575](https://github.com/matrix-org/synapse/issues/10575), [\#10579](https://github.com/matrix-org/synapse/issues/10579), [\#10583](https://github.com/matrix-org/synapse/issues/10583))
- Admin API to delete several media for a specific user. Contributed by @dklimpel. ([\#10558](https://github.com/matrix-org/synapse/issues/10558), [\#10628](https://github.com/matrix-org/synapse/issues/10628))
- Add support for routing `/createRoom` to workers. ([\#10564](https://github.com/matrix-org/synapse/issues/10564))
- Update the Synapse Grafana dashboard. ([\#10570](https://github.com/matrix-org/synapse/issues/10570))
- Add an admin API (`GET /_synapse/admin/username_available`) to check if a username is available (regardless of registration settings). ([\#10578](https://github.com/matrix-org/synapse/issues/10578))
- Allow editing a user's `external_ids` via the "Edit User" admin API. Contributed by @dklimpel. ([\#10598](https://github.com/matrix-org/synapse/issues/10598))
- The Synapse manhole no longer needs coroutines to be wrapped in `defer.ensureDeferred`. ([\#10602](https://github.com/matrix-org/synapse/issues/10602))
- Add option to allow modules to run periodic tasks on all instances, rather than just the one configured to run background tasks. ([\#10638](https://github.com/matrix-org/synapse/issues/10638))


Bugfixes
--------

- Add some clarification to the sample config file. Contributed by @Kentokamoto. ([\#10129](https://github.com/matrix-org/synapse/issues/10129))
- Fix a long-standing bug where protocols which are not implemented by any appservices were incorrectly returned via `GET /_matrix/client/r0/thirdparty/protocols`. ([\#10532](https://github.com/matrix-org/synapse/issues/10532))
- Fix exceptions in logs when failing to get remote room list. ([\#10541](https://github.com/matrix-org/synapse/issues/10541))
- Fix longstanding bug which caused the user's presence "status message" to be reset when the user went offline. Contributed by @dklimpel. ([\#10550](https://github.com/matrix-org/synapse/issues/10550))
- Allow public rooms to be previewed in the spaces summary APIs from [MSC2946](https://github.com/matrix-org/matrix-doc/pull/2946). ([\#10580](https://github.com/matrix-org/synapse/issues/10580))
- Fix a bug introduced in v1.37.1 where an error could occur in the asynchronous processing of PDUs when the queue was empty. ([\#10592](https://github.com/matrix-org/synapse/issues/10592))
- Fix errors on /sync when read receipt data is a string. Only affects homeservers with the experimental flag for [MSC2285](https://github.com/matrix-org/matrix-doc/pull/2285) enabled. Contributed by @SimonBrandner. ([\#10606](https://github.com/matrix-org/synapse/issues/10606))
- Additional validation for the spaces summary API to avoid errors like `ValueError: Stop argument for islice() must be None or an integer`. The missing validation has existed since v1.31.0. ([\#10611](https://github.com/matrix-org/synapse/issues/10611))
- Revert behaviour introduced in v1.38.0 that strips `org.matrix.msc2732.device_unused_fallback_key_types` from `/sync` when its value is empty. This field should instead always be present according to [MSC2732](https://github.com/matrix-org/matrix-doc/blob/master/proposals/2732-olm-fallback-keys.md). ([\#10623](https://github.com/matrix-org/synapse/issues/10623))


Improved Documentation
----------------------

- Add documentation for configuring a forward proxy. ([\#10443](https://github.com/matrix-org/synapse/issues/10443))
- Updated the reverse proxy documentation to highlight the homserver configuration that is needed to make Synapse aware that is is intentionally reverse proxied. ([\#10551](https://github.com/matrix-org/synapse/issues/10551))
- Update CONTRIBUTING.md to fix index links and the instructions for SyTest in docker. ([\#10599](https://github.com/matrix-org/synapse/issues/10599))


Deprecations and Removals
-------------------------

- No longer build `.deb` packages for Ubuntu 20.10 Groovy Gorilla, which has now EOLed. ([\#10588](https://github.com/matrix-org/synapse/issues/10588))
- The `template_dir` configuration settings in the `sso`, `account_validity` and `email` sections of the configuration file are now deprecated in favour of the global `templates.custom_template_directory` setting. See the [upgrade notes](https://matrix-org.github.io/synapse/latest/upgrade.html) for more information. ([\#10596](https://github.com/matrix-org/synapse/issues/10596))


Internal Changes
----------------

- Improve event caching mechanism to avoid having multiple copies of an event in memory at a time. ([\#10119](https://github.com/matrix-org/synapse/issues/10119))
- Reduce errors in PostgreSQL logs due to concurrent serialization errors. ([\#10504](https://github.com/matrix-org/synapse/issues/10504))
- Include room ID in ignored EDU log messages. Contributed by @ilmari. ([\#10507](https://github.com/matrix-org/synapse/issues/10507))
- Add pagination to the spaces summary based on updates to [MSC2946](https://github.com/matrix-org/matrix-doc/pull/2946). ([\#10527](https://github.com/matrix-org/synapse/issues/10527), [\#10530](https://github.com/matrix-org/synapse/issues/10530))
- Fix CI to not break when run against branches rather than pull requests. ([\#10529](https://github.com/matrix-org/synapse/issues/10529))
- Mark all events stemming from the [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) `/batch_send` endpoint as historical. ([\#10537](https://github.com/matrix-org/synapse/issues/10537))
- Clean up some of the federation event authentication code for clarity. ([\#10539](https://github.com/matrix-org/synapse/issues/10539), [\#10591](https://github.com/matrix-org/synapse/issues/10591))
- Convert `Transaction` and `Edu` objects to attrs. ([\#10542](https://github.com/matrix-org/synapse/issues/10542))
- Update `/batch_send` endpoint to only return `state_events` created by the `state_events_from_before` passed in. ([\#10552](https://github.com/matrix-org/synapse/issues/10552))
- Update contributing.md to warn against rebasing an open PR. ([\#10563](https://github.com/matrix-org/synapse/issues/10563))
- Remove the unused public rooms replication stream. ([\#10565](https://github.com/matrix-org/synapse/issues/10565))
- Clarify error message when failing to join a restricted room. ([\#10572](https://github.com/matrix-org/synapse/issues/10572))
- Remove references to BuildKite in favour of GitHub Actions. ([\#10573](https://github.com/matrix-org/synapse/issues/10573))
- Move `/batch_send` endpoint defined by [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) to the `/v2_alpha` directory. ([\#10576](https://github.com/matrix-org/synapse/issues/10576))
- Allow multiple custom directories in `read_templates`. ([\#10587](https://github.com/matrix-org/synapse/issues/10587))
- Re-organize the `synapse.federation.transport.server` module to create smaller files. ([\#10590](https://github.com/matrix-org/synapse/issues/10590))
- Flatten the `synapse.rest.client` package by moving the contents of `v1` and `v2_alpha` into the parent. ([\#10600](https://github.com/matrix-org/synapse/issues/10600))
- Build Debian packages for Debian 12 (Bookworm). ([\#10612](https://github.com/matrix-org/synapse/issues/10612))
- Fix up a couple of links to the database schema documentation. ([\#10620](https://github.com/matrix-org/synapse/issues/10620))
- Fix a broken link to the upgrade notes. ([\#10631](https://github.com/matrix-org/synapse/issues/10631))


Synapse 1.40.0 (2021-08-10)
===========================

No significant changes.


Synapse 1.40.0rc3 (2021-08-09)
==============================

Features
--------

- Support [MSC3289: room version 8](https://github.com/matrix-org/matrix-doc/pull/3289). ([\#10449](https://github.com/matrix-org/synapse/issues/10449))


Bugfixes
--------

- Mark the experimental room version from [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) as unstable. ([\#10449](https://github.com/matrix-org/synapse/issues/10449))


Improved Documentation
----------------------

- Fix broken links in `upgrade.md`. Contributed by @dklimpel. ([\#10543](https://github.com/matrix-org/synapse/issues/10543))


Synapse 1.40.0rc2 (2021-08-04)
==============================

Bugfixes
--------

- Fix the `PeriodicallyFlushingMemoryHandler` inhibiting application shutdown because of its background thread. ([\#10517](https://github.com/matrix-org/synapse/issues/10517))
- Fix a bug introduced in Synapse v1.40.0rc1 that could cause Synapse to respond with an error when clients would update read receipts. ([\#10531](https://github.com/matrix-org/synapse/issues/10531))


Internal Changes
----------------

- Fix release script to open the correct URL for the release. ([\#10516](https://github.com/matrix-org/synapse/issues/10516))


Synapse 1.40.0rc1 (2021-08-03)
==============================

Features
--------

- Add support for [MSC2033](https://github.com/matrix-org/matrix-doc/pull/2033): `device_id` on `/account/whoami`. ([\#9918](https://github.com/matrix-org/synapse/issues/9918))
- Update support for [MSC2716 - Incrementally importing history into existing rooms](https://github.com/matrix-org/matrix-doc/pull/2716). ([\#10245](https://github.com/matrix-org/synapse/issues/10245), [\#10432](https://github.com/matrix-org/synapse/issues/10432), [\#10463](https://github.com/matrix-org/synapse/issues/10463))
- Update support for [MSC3083](https://github.com/matrix-org/matrix-doc/pull/3083) to consider changes in the MSC around which servers can issue join events. ([\#10254](https://github.com/matrix-org/synapse/issues/10254), [\#10447](https://github.com/matrix-org/synapse/issues/10447), [\#10489](https://github.com/matrix-org/synapse/issues/10489))
- Initial support for [MSC3244](https://github.com/matrix-org/matrix-doc/pull/3244), Room version capabilities over the /capabilities API. ([\#10283](https://github.com/matrix-org/synapse/issues/10283))
- Add a buffered logging handler which periodically flushes itself. ([\#10407](https://github.com/matrix-org/synapse/issues/10407), [\#10515](https://github.com/matrix-org/synapse/issues/10515))
- Add support for https connections to a proxy server. Contributed by @Bubu and @dklimpel. ([\#10411](https://github.com/matrix-org/synapse/issues/10411))
- Support for [MSC2285 (hidden read receipts)](https://github.com/matrix-org/matrix-doc/pull/2285). Contributed by @SimonBrandner. ([\#10413](https://github.com/matrix-org/synapse/issues/10413))
- Email notifications now state whether an invitation is to a room or a space. ([\#10426](https://github.com/matrix-org/synapse/issues/10426))
- Allow setting transaction limit for database connections. ([\#10440](https://github.com/matrix-org/synapse/issues/10440), [\#10511](https://github.com/matrix-org/synapse/issues/10511))
- Add `creation_ts` to "list users" admin API. ([\#10448](https://github.com/matrix-org/synapse/issues/10448))


Bugfixes
--------

- Improve character set detection in URL previews by supporting underscores (in addition to hyphens). Contributed by @srividyut. ([\#10410](https://github.com/matrix-org/synapse/issues/10410))
- Fix events being incorrectly rejected over federation if they reference auth events that the server needed to fetch. ([\#10439](https://github.com/matrix-org/synapse/issues/10439))
- Fix `synapse_federation_server_oldest_inbound_pdu_in_staging` Prometheus metric to not report a max age of 51 years when the queue is empty. ([\#10455](https://github.com/matrix-org/synapse/issues/10455))
- Fix a bug which caused an explicit assignment of power-level 0 to a user to be misinterpreted in rare circumstances. ([\#10499](https://github.com/matrix-org/synapse/issues/10499))


Improved Documentation
----------------------

- Fix hierarchy of providers on the OpenID page. ([\#10445](https://github.com/matrix-org/synapse/issues/10445))
- Consolidate development documentation to `docs/development/`. ([\#10453](https://github.com/matrix-org/synapse/issues/10453))
- Add some developer docs to explain room DAG concepts like `outliers`, `state_groups`, `depth`, etc. ([\#10464](https://github.com/matrix-org/synapse/issues/10464))
- Document how to use Complement while developing a new Synapse feature. ([\#10483](https://github.com/matrix-org/synapse/issues/10483))


Internal Changes
----------------

- Prune inbound federation queues for a room if they get too large. ([\#10390](https://github.com/matrix-org/synapse/issues/10390))
- Add type hints to `synapse.federation.transport.client` module. ([\#10408](https://github.com/matrix-org/synapse/issues/10408))
- Remove shebang line from module files. ([\#10415](https://github.com/matrix-org/synapse/issues/10415))
- Drop backwards-compatibility code that was required to support Ubuntu Xenial. ([\#10429](https://github.com/matrix-org/synapse/issues/10429))
- Use a docker image cache for the prerequisites for the debian package build. ([\#10431](https://github.com/matrix-org/synapse/issues/10431))
- Improve servlet type hints. ([\#10437](https://github.com/matrix-org/synapse/issues/10437), [\#10438](https://github.com/matrix-org/synapse/issues/10438))
- Replace usage of `or_ignore` in `simple_insert` with `simple_upsert` usage, to stop spamming postgres logs with spurious ERROR messages. ([\#10442](https://github.com/matrix-org/synapse/issues/10442))
- Update the `tests-done` Github Actions status. ([\#10444](https://github.com/matrix-org/synapse/issues/10444), [\#10512](https://github.com/matrix-org/synapse/issues/10512))
- Update type annotations to work with forthcoming Twisted 21.7.0 release. ([\#10446](https://github.com/matrix-org/synapse/issues/10446), [\#10450](https://github.com/matrix-org/synapse/issues/10450))
- Cancel redundant GHA workflows when a new commit is pushed. ([\#10451](https://github.com/matrix-org/synapse/issues/10451))
- Mitigate media repo XSS attacks on IE11 via the non-standard X-Content-Security-Policy header. ([\#10468](https://github.com/matrix-org/synapse/issues/10468))
- Additional type hints in the state handler. ([\#10482](https://github.com/matrix-org/synapse/issues/10482))
- Update syntax used to run complement tests. ([\#10488](https://github.com/matrix-org/synapse/issues/10488))
- Fix up type annotations to work with Twisted 21.7. ([\#10490](https://github.com/matrix-org/synapse/issues/10490))
- Improve type annotations for `ObservableDeferred`. ([\#10491](https://github.com/matrix-org/synapse/issues/10491))
- Extend release script to also tag and create GitHub releases. ([\#10496](https://github.com/matrix-org/synapse/issues/10496))
- Fix a bug which caused production debian packages to be incorrectly marked as 'prerelease'. ([\#10500](https://github.com/matrix-org/synapse/issues/10500))


Synapse 1.39.0 (2021-07-29)
===========================

No significant changes.


Synapse 1.39.0rc3 (2021-07-28)
==============================

Bugfixes
--------

- Fix a bug introduced in Synapse 1.38 which caused an exception at startup when SAML authentication was enabled. ([\#10477](https://github.com/matrix-org/synapse/issues/10477))
- Fix a long-standing bug where Synapse would not inform clients that a device had exhausted its one-time-key pool, potentially causing problems decrypting events. ([\#10485](https://github.com/matrix-org/synapse/issues/10485))
- Fix reporting old R30 stats as R30v2 stats. Introduced in v1.39.0rc1. ([\#10486](https://github.com/matrix-org/synapse/issues/10486))


Internal Changes
----------------

- Fix an error which prevented the Github Actions workflow to build the docker images from running. ([\#10461](https://github.com/matrix-org/synapse/issues/10461))
- Fix release script to correctly version debian changelog when doing RCs. ([\#10465](https://github.com/matrix-org/synapse/issues/10465))


Synapse 1.39.0rc2 (2021-07-22)
==============================

This release also includes the changes in v1.38.1.


Internal Changes
----------------

- Move docker image build to Github Actions. ([\#10416](https://github.com/matrix-org/synapse/issues/10416))


Synapse 1.38.1 (2021-07-22)
===========================

Bugfixes
--------

- Always include `device_one_time_keys_count` key in `/sync` response to work around a bug in Element Android that broke encryption for new devices. ([\#10457](https://github.com/matrix-org/synapse/issues/10457))


Synapse 1.39.0rc1 (2021-07-20)
==============================

The Third-Party Event Rules module interface has been deprecated in favour of the generic module interface introduced in Synapse v1.37.0. Support for the old interface is planned to be removed in September 2021. See the [upgrade notes](https://matrix-org.github.io/synapse/latest/upgrade.html#upgrading-to-v1390) for more information.

Features
--------

- Add the ability to override the account validity feature with a module. ([\#9884](https://github.com/matrix-org/synapse/issues/9884))
- The spaces summary API now returns any joinable rooms, not only rooms which are world-readable. ([\#10298](https://github.com/matrix-org/synapse/issues/10298), [\#10305](https://github.com/matrix-org/synapse/issues/10305))
- Add a new version of the R30 phone-home metric, which removes a false impression of retention given by the old R30 metric. ([\#10332](https://github.com/matrix-org/synapse/issues/10332), [\#10427](https://github.com/matrix-org/synapse/issues/10427))
- Allow providing credentials to `http_proxy`. ([\#10360](https://github.com/matrix-org/synapse/issues/10360))


Bugfixes
--------

- Fix error while dropping locks on shutdown. Introduced in v1.38.0. ([\#10433](https://github.com/matrix-org/synapse/issues/10433))
- Add base starting insertion event when no chunk ID is specified in the historical batch send API. ([\#10250](https://github.com/matrix-org/synapse/issues/10250))
- Fix historical batch send endpoint (MSC2716) rejecting batches with messages from multiple senders. ([\#10276](https://github.com/matrix-org/synapse/issues/10276))
- Fix purging rooms that other homeservers are still sending events for. Contributed by @ilmari. ([\#10317](https://github.com/matrix-org/synapse/issues/10317))
- Fix errors during backfill caused by previously purged redaction events. Contributed by Andreas Rammhold (@andir). ([\#10343](https://github.com/matrix-org/synapse/issues/10343))
- Fix the user directory becoming broken (and noisy errors being logged) when knocking and room statistics are in use. ([\#10344](https://github.com/matrix-org/synapse/issues/10344))
- Fix newly added `synapse_federation_server_oldest_inbound_pdu_in_staging` prometheus metric to measure age rather than timestamp. ([\#10355](https://github.com/matrix-org/synapse/issues/10355))
- Fix PostgreSQL sometimes using table scans for queries against `state_groups_state` table, taking a long time and a large amount of IO. ([\#10359](https://github.com/matrix-org/synapse/issues/10359))
- Fix `make_room_admin` failing for users that have left a private room. ([\#10367](https://github.com/matrix-org/synapse/issues/10367))
- Fix a number of logged errors caused by remote servers being down. ([\#10400](https://github.com/matrix-org/synapse/issues/10400), [\#10414](https://github.com/matrix-org/synapse/issues/10414))
- Responses from `/make_{join,leave,knock}` no longer include signatures, which will turn out to be invalid after events are returned to `/send_{join,leave,knock}`. ([\#10404](https://github.com/matrix-org/synapse/issues/10404))


Improved Documentation
----------------------

- Updated installation dependencies for newer macOS versions and ARM Macs. Contributed by Luke Walsh. ([\#9971](https://github.com/matrix-org/synapse/issues/9971))
- Simplify structure of room admin API. ([\#10313](https://github.com/matrix-org/synapse/issues/10313))
- Refresh the logcontext dev documentation. ([\#10353](https://github.com/matrix-org/synapse/issues/10353)), ([\#10337](https://github.com/matrix-org/synapse/issues/10337))
- Add delegation example for caddy in the reverse proxy documentation. Contributed by @moritzdietz. ([\#10368](https://github.com/matrix-org/synapse/issues/10368))
- Fix and clarify some links in `docs` and `contrib`. ([\#10370](https://github.com/matrix-org/synapse/issues/10370)), ([\#10322](https://github.com/matrix-org/synapse/issues/10322)), ([\#10399](https://github.com/matrix-org/synapse/issues/10399))
- Make deprecation notice of the spam checker doc more obvious. ([\#10395](https://github.com/matrix-org/synapse/issues/10395))
- Add instructions on installing Debian packages for release candidates. ([\#10396](https://github.com/matrix-org/synapse/issues/10396))


Deprecations and Removals
-------------------------

- Remove functionality associated with the unused `room_stats_historical` and `user_stats_historical` tables. Contributed by @xmunoz. ([\#9721](https://github.com/matrix-org/synapse/issues/9721))
- The third-party event rules module interface is deprecated in favour of the generic module interface introduced in Synapse v1.37.0. See the [upgrade notes](https://matrix-org.github.io/synapse/latest/upgrade.html#upgrading-to-v1390) for more information. ([\#10386](https://github.com/matrix-org/synapse/issues/10386))


Internal Changes
----------------

- Convert `room_depth.min_depth` column to a `BIGINT`. ([\#10289](https://github.com/matrix-org/synapse/issues/10289))
- Add tests to characterise the current behaviour of R30 phone-home metrics. ([\#10315](https://github.com/matrix-org/synapse/issues/10315))
- Rebuild event context and auth when processing specific results from `ThirdPartyEventRules` modules. ([\#10316](https://github.com/matrix-org/synapse/issues/10316))
- Minor change to the code that populates `user_daily_visits`. ([\#10324](https://github.com/matrix-org/synapse/issues/10324))
- Re-enable Sytests that were disabled for the 1.37.1 release. ([\#10345](https://github.com/matrix-org/synapse/issues/10345), [\#10357](https://github.com/matrix-org/synapse/issues/10357))
- Run `pyupgrade` on the codebase. ([\#10347](https://github.com/matrix-org/synapse/issues/10347), [\#10348](https://github.com/matrix-org/synapse/issues/10348))
- Switch `application_services_txns.txn_id` database column to `BIGINT`. ([\#10349](https://github.com/matrix-org/synapse/issues/10349))
- Convert internal type variable syntax to reflect wider ecosystem use. ([\#10350](https://github.com/matrix-org/synapse/issues/10350), [\#10380](https://github.com/matrix-org/synapse/issues/10380), [\#10381](https://github.com/matrix-org/synapse/issues/10381), [\#10382](https://github.com/matrix-org/synapse/issues/10382), [\#10418](https://github.com/matrix-org/synapse/issues/10418))
- Make the Github Actions workflow configuration more efficient. ([\#10383](https://github.com/matrix-org/synapse/issues/10383))
- Add type hints to `get_{domain,localpart}_from_id`. ([\#10385](https://github.com/matrix-org/synapse/issues/10385))
- When building Debian packages for prerelease versions, set the Section accordingly. ([\#10391](https://github.com/matrix-org/synapse/issues/10391))
- Add type hints and comments to event auth code. ([\#10393](https://github.com/matrix-org/synapse/issues/10393))
- Stagger sending of presence update to remote servers, reducing CPU spikes caused by starting many connections to remote servers at once. ([\#10398](https://github.com/matrix-org/synapse/issues/10398))
- Remove unused `events_by_room` code (tech debt). ([\#10421](https://github.com/matrix-org/synapse/issues/10421))
- Add a github actions job which records success of other jobs. ([\#10430](https://github.com/matrix-org/synapse/issues/10430))


Synapse 1.38.0 (2021-07-13)
===========================

This release includes a database schema update which could result in elevated disk usage. See the [upgrade notes](https://matrix-org.github.io/synapse/develop/upgrade#upgrading-to-v1380) for more information.

No significant changes since 1.38.0rc3.


Synapse 1.38.0rc3 (2021-07-13)
==============================

Internal Changes
----------------

- Build the Debian packages in CI. ([\#10247](https://github.com/matrix-org/synapse/issues/10247), [\#10379](https://github.com/matrix-org/synapse/issues/10379))


Synapse 1.38.0rc2 (2021-07-09)
==============================

Bugfixes
--------

- Fix bug where inbound federation in a room could be delayed due to not correctly dropping a lock. Introduced in v1.37.1. ([\#10336](https://github.com/matrix-org/synapse/issues/10336))


Improved Documentation
----------------------

- Update links to documentation in the sample config. Contributed by @dklimpel. ([\#10287](https://github.com/matrix-org/synapse/issues/10287))
- Fix broken links in [INSTALL.md](INSTALL.md). Contributed by @dklimpel. ([\#10331](https://github.com/matrix-org/synapse/issues/10331))


Synapse 1.38.0rc1 (2021-07-06)
==============================

Features
--------

- Implement refresh tokens as specified by [MSC2918](https://github.com/matrix-org/matrix-doc/pull/2918). ([\#9450](https://github.com/matrix-org/synapse/issues/9450))
- Add support for evicting cache entries based on last access time. ([\#10205](https://github.com/matrix-org/synapse/issues/10205))
- Omit empty fields from the `/sync` response. Contributed by @deepbluev7. ([\#10214](https://github.com/matrix-org/synapse/issues/10214))
- Improve validation on federation `send_{join,leave,knock}` endpoints. ([\#10225](https://github.com/matrix-org/synapse/issues/10225), [\#10243](https://github.com/matrix-org/synapse/issues/10243))
- Add SSO `external_ids` to the Query User Account admin API. ([\#10261](https://github.com/matrix-org/synapse/issues/10261))
- Mark events received over federation which fail a spam check as "soft-failed". ([\#10263](https://github.com/matrix-org/synapse/issues/10263))
- Add metrics for new inbound federation staging area. ([\#10284](https://github.com/matrix-org/synapse/issues/10284))
- Add script to print information about recently registered users. ([\#10290](https://github.com/matrix-org/synapse/issues/10290))


Bugfixes
--------

- Fix a long-standing bug which meant that invite rejections and knocks were not sent out over federation in a timely manner. ([\#10223](https://github.com/matrix-org/synapse/issues/10223))
- Fix a bug introduced in v1.26.0 where only users who have set profile information could be deactivated with erasure enabled. ([\#10252](https://github.com/matrix-org/synapse/issues/10252))
- Fix a long-standing bug where Synapse would return errors after 2<sup>31</sup> events were handled by the server. ([\#10264](https://github.com/matrix-org/synapse/issues/10264), [\#10267](https://github.com/matrix-org/synapse/issues/10267), [\#10282](https://github.com/matrix-org/synapse/issues/10282), [\#10286](https://github.com/matrix-org/synapse/issues/10286), [\#10291](https://github.com/matrix-org/synapse/issues/10291), [\#10314](https://github.com/matrix-org/synapse/issues/10314), [\#10326](https://github.com/matrix-org/synapse/issues/10326))
- Fix the prometheus `synapse_federation_server_pdu_process_time` metric. Broke in v1.37.1. ([\#10279](https://github.com/matrix-org/synapse/issues/10279))
- Ensure that inbound events from federation that were being processed when Synapse was restarted get promptly processed on start up. ([\#10303](https://github.com/matrix-org/synapse/issues/10303))


Improved Documentation
----------------------

- Move the upgrade notes to [docs/upgrade.md](https://github.com/matrix-org/synapse/blob/develop/docs/upgrade.md) and convert them to markdown. ([\#10166](https://github.com/matrix-org/synapse/issues/10166))
- Choose Welcome & Overview as the default page for synapse documentation website. ([\#10242](https://github.com/matrix-org/synapse/issues/10242))
- Adjust the URL in the README.rst file to point to irc.libera.chat. ([\#10258](https://github.com/matrix-org/synapse/issues/10258))
- Fix homeserver config option name in presence router documentation. ([\#10288](https://github.com/matrix-org/synapse/issues/10288))
- Fix link pointing at the wrong section in the modules documentation page. ([\#10302](https://github.com/matrix-org/synapse/issues/10302))


Internal Changes
----------------

- Drop `Origin` and `Accept` from the value of the `Access-Control-Allow-Headers` response header. ([\#10114](https://github.com/matrix-org/synapse/issues/10114))
- Add type hints to the federation servlets. ([\#10213](https://github.com/matrix-org/synapse/issues/10213))
- Improve the reliability of auto-joining remote rooms. ([\#10237](https://github.com/matrix-org/synapse/issues/10237))
- Update the release script to use the semver terminology and determine the release branch based on the next version. ([\#10239](https://github.com/matrix-org/synapse/issues/10239))
- Fix type hints for computing auth events. ([\#10253](https://github.com/matrix-org/synapse/issues/10253))
- Improve the performance of the spaces summary endpoint by only recursing into spaces (and not rooms in general). ([\#10256](https://github.com/matrix-org/synapse/issues/10256))
- Move event authentication methods from `Auth` to `EventAuthHandler`. ([\#10268](https://github.com/matrix-org/synapse/issues/10268))
- Re-enable a SyTest after it has been fixed. ([\#10292](https://github.com/matrix-org/synapse/issues/10292))


Synapse 1.37.1 (2021-06-30)
===========================

This release resolves issues (such as [#9490](https://github.com/matrix-org/synapse/issues/9490)) where one busy room could cause head-of-line blocking, starving Synapse from processing events in other rooms, and causing all federated traffic to fall behind. Synapse 1.37.1 processes inbound federation traffic asynchronously, ensuring that one busy room won't impact others. Please upgrade to Synapse 1.37.1 as soon as possible, in order to increase resilience to other traffic spikes.

No significant changes since v1.37.1rc1.


Synapse 1.37.1rc1 (2021-06-29)
==============================

Features
--------

- Handle inbound events from federation asynchronously. ([\#10269](https://github.com/matrix-org/synapse/issues/10269), [\#10272](https://github.com/matrix-org/synapse/issues/10272))


Synapse 1.37.0 (2021-06-29)
===========================

This release deprecates the current spam checker interface. See the [upgrade notes](https://matrix-org.github.io/synapse/develop/upgrade#deprecation-of-the-current-spam-checker-interface) for more information on how to update to the new generic module interface.

This release also removes support for fetching and renewing TLS certificates using the ACME v1 protocol, which has been fully decommissioned by Let's Encrypt on June 1st 2021. Admins previously using this feature should use a [reverse proxy](https://matrix-org.github.io/synapse/develop/reverse_proxy.html) to handle TLS termination, or use an external ACME client (such as [certbot](https://certbot.eff.org/)) to retrieve a certificate and key and provide them to Synapse using the `tls_certificate_path` and `tls_private_key_path` configuration settings.

Synapse 1.37.0rc1 (2021-06-24)
==============================

Features
--------

- Implement "room knocking" as per [MSC2403](https://github.com/matrix-org/matrix-doc/pull/2403). Contributed by @Sorunome and anoa. ([\#6739](https://github.com/matrix-org/synapse/issues/6739), [\#9359](https://github.com/matrix-org/synapse/issues/9359), [\#10167](https://github.com/matrix-org/synapse/issues/10167), [\#10212](https://github.com/matrix-org/synapse/issues/10212), [\#10227](https://github.com/matrix-org/synapse/issues/10227))
- Add experimental support for backfilling history into rooms ([MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716)). ([\#9247](https://github.com/matrix-org/synapse/issues/9247))
- Implement a generic interface for third-party plugin modules. ([\#10062](https://github.com/matrix-org/synapse/issues/10062), [\#10206](https://github.com/matrix-org/synapse/issues/10206))
- Implement config option `sso.update_profile_information` to sync SSO users' profile information with the identity provider each time they login. Currently only displayname is supported. ([\#10108](https://github.com/matrix-org/synapse/issues/10108))
- Ensure that errors during startup are written to the logs and the console. ([\#10191](https://github.com/matrix-org/synapse/issues/10191))


Bugfixes
--------

- Fix a bug introduced in Synapse v1.25.0 that prevented the `ip_range_whitelist` configuration option from working for federation and identity servers. Contributed by @mikure. ([\#10115](https://github.com/matrix-org/synapse/issues/10115))
- Remove a broken import line in Synapse's `admin_cmd` worker. Broke in Synapse v1.33.0. ([\#10154](https://github.com/matrix-org/synapse/issues/10154))
- Fix a bug introduced in Synapse v1.21.0 which could cause `/sync` to return immediately with an empty response. ([\#10157](https://github.com/matrix-org/synapse/issues/10157), [\#10158](https://github.com/matrix-org/synapse/issues/10158))
- Fix a minor bug in the response to `/_matrix/client/r0/user/{user}/openid/request_token` causing `expires_in` to be a float instead of an integer. Contributed by @lukaslihotzki. ([\#10175](https://github.com/matrix-org/synapse/issues/10175))
- Always require users to re-authenticate for dangerous operations: deactivating an account, modifying an account password, and adding 3PIDs. ([\#10184](https://github.com/matrix-org/synapse/issues/10184))
- Fix a bug introduced in Synpase v1.7.2 where remote server count metrics collection would be incorrectly delayed on startup. Found by @heftig. ([\#10195](https://github.com/matrix-org/synapse/issues/10195))
- Fix a bug introduced in Synapse v1.35.1 where an `allow` key of a `m.room.join_rules` event could be applied for incorrect room versions and configurations. ([\#10208](https://github.com/matrix-org/synapse/issues/10208))
- Fix performance regression in responding to user key requests over federation. Introduced in Synapse v1.34.0rc1. ([\#10221](https://github.com/matrix-org/synapse/issues/10221))


Improved Documentation
----------------------

- Add a new guide to decoding request logs. ([\#8436](https://github.com/matrix-org/synapse/issues/8436))
- Mention in the sample homeserver config that you may need to configure max upload size in your reverse proxy. Contributed by @aaronraimist. ([\#10122](https://github.com/matrix-org/synapse/issues/10122))
- Fix broken links in documentation. ([\#10180](https://github.com/matrix-org/synapse/issues/10180))
- Deploy a snapshot of the documentation website upon each new Synapse release. ([\#10198](https://github.com/matrix-org/synapse/issues/10198))


Deprecations and Removals
-------------------------

- The current spam checker interface is deprecated in favour of a new generic modules system. See the [upgrade notes](https://matrix-org.github.io/synapse/develop/upgrade#deprecation-of-the-current-spam-checker-interface) for more information on how to update to the new system. ([\#10062](https://github.com/matrix-org/synapse/issues/10062), [\#10210](https://github.com/matrix-org/synapse/issues/10210), [\#10238](https://github.com/matrix-org/synapse/issues/10238))
- Stop supporting the unstable spaces prefixes from MSC1772. ([\#10161](https://github.com/matrix-org/synapse/issues/10161))
- Remove Synapse's support for automatically fetching and renewing certificates using the ACME v1 protocol. This protocol has been fully turned off by Let's Encrypt for existing installations on June 1st 2021. Admins previously using this feature should use a [reverse proxy](https://matrix-org.github.io/synapse/develop/reverse_proxy.html) to handle TLS termination, or use an external ACME client (such as [certbot](https://certbot.eff.org/)) to retrieve a certificate and key and provide them to Synapse using the `tls_certificate_path` and `tls_private_key_path` configuration settings. ([\#10194](https://github.com/matrix-org/synapse/issues/10194))


Internal Changes
----------------

- Update the database schema versioning to support gradual migration away from legacy tables. ([\#9933](https://github.com/matrix-org/synapse/issues/9933))
- Add type hints to the federation servlets. ([\#10080](https://github.com/matrix-org/synapse/issues/10080))
- Improve OpenTracing for event persistence. ([\#10134](https://github.com/matrix-org/synapse/issues/10134), [\#10193](https://github.com/matrix-org/synapse/issues/10193))
- Clean up the interface for injecting OpenTracing over HTTP. ([\#10143](https://github.com/matrix-org/synapse/issues/10143))
- Limit the number of in-flight `/keys/query` requests from a single device. ([\#10144](https://github.com/matrix-org/synapse/issues/10144))
- Refactor EventPersistenceQueue. ([\#10145](https://github.com/matrix-org/synapse/issues/10145))
- Document `SYNAPSE_TEST_LOG_LEVEL` to see the logger output when running tests. ([\#10148](https://github.com/matrix-org/synapse/issues/10148))
- Update the Complement build tags in GitHub Actions to test currently experimental features. ([\#10155](https://github.com/matrix-org/synapse/issues/10155))
- Add a `synapse_federation_soft_failed_events_total` metric to track how often events are soft failed. ([\#10156](https://github.com/matrix-org/synapse/issues/10156))
- Fetch the corresponding complement branch when performing CI. ([\#10160](https://github.com/matrix-org/synapse/issues/10160))
- Add some developer documentation about boolean columns in database schemas. ([\#10164](https://github.com/matrix-org/synapse/issues/10164))
- Add extra logging fields to better debug where events are being soft failed. ([\#10168](https://github.com/matrix-org/synapse/issues/10168))
- Add debug logging for when we enter and exit `Measure` blocks. ([\#10183](https://github.com/matrix-org/synapse/issues/10183))
- Improve comments in structured logging code. ([\#10188](https://github.com/matrix-org/synapse/issues/10188))
- Update [MSC3083](https://github.com/matrix-org/matrix-doc/pull/3083) support with modifications from the MSC. ([\#10189](https://github.com/matrix-org/synapse/issues/10189))
- Remove redundant DNS lookup limiter. ([\#10190](https://github.com/matrix-org/synapse/issues/10190))
- Upgrade `black` linting tool to 21.6b0. ([\#10197](https://github.com/matrix-org/synapse/issues/10197))
- Expose OpenTracing trace id in response headers. ([\#10199](https://github.com/matrix-org/synapse/issues/10199))


Synapse 1.36.0 (2021-06-15)
===========================

No significant changes.


Synapse 1.36.0rc2 (2021-06-11)
==============================

Bugfixes
--------

- Fix a bug which caused  presence updates to stop working some time after a restart, when using a presence writer worker. Broke in v1.33.0. ([\#10149](https://github.com/matrix-org/synapse/issues/10149))
- Fix a bug when using federation sender worker where it would send out more presence updates than necessary, leading to high resource usage. Broke in v1.33.0. ([\#10163](https://github.com/matrix-org/synapse/issues/10163))
- Fix a bug where Synapse could send the same presence update to a remote twice. ([\#10165](https://github.com/matrix-org/synapse/issues/10165))


Synapse 1.36.0rc1 (2021-06-08)
==============================

Features
--------

- Add new endpoint `/_matrix/client/r0/rooms/{roomId}/aliases` from Client-Server API r0.6.1 (previously [MSC2432](https://github.com/matrix-org/matrix-doc/pull/2432)). ([\#9224](https://github.com/matrix-org/synapse/issues/9224))
- Improve performance of incoming federation transactions in large rooms. ([\#9953](https://github.com/matrix-org/synapse/issues/9953), [\#9973](https://github.com/matrix-org/synapse/issues/9973))
- Rewrite logic around verifying JSON object and fetching server keys to be more performant and use less memory. ([\#10035](https://github.com/matrix-org/synapse/issues/10035))
- Add new admin APIs for unprotecting local media from quarantine. Contributed by @dklimpel. ([\#10040](https://github.com/matrix-org/synapse/issues/10040))
- Add new admin APIs to remove media by media ID from quarantine. Contributed by @dklimpel. ([\#10044](https://github.com/matrix-org/synapse/issues/10044))
- Make reason and score parameters optional for reporting content. Implements [MSC2414](https://github.com/matrix-org/matrix-doc/pull/2414). Contributed by Callum Brown. ([\#10077](https://github.com/matrix-org/synapse/issues/10077))
- Add support for routing more requests to workers. ([\#10084](https://github.com/matrix-org/synapse/issues/10084))
- Report OpenTracing spans for database activity. ([\#10113](https://github.com/matrix-org/synapse/issues/10113), [\#10136](https://github.com/matrix-org/synapse/issues/10136), [\#10141](https://github.com/matrix-org/synapse/issues/10141))
- Significantly reduce memory usage of joining large remote rooms. ([\#10117](https://github.com/matrix-org/synapse/issues/10117))


Bugfixes
--------

- Fixed a bug causing replication requests to fail when receiving a lot of events via federation. ([\#10082](https://github.com/matrix-org/synapse/issues/10082))
- Fix a bug in the `force_tracing_for_users` option introduced in Synapse v1.35 which meant that the OpenTracing spans produced were missing most tags. ([\#10092](https://github.com/matrix-org/synapse/issues/10092))
- Fixed a bug that could cause Synapse to stop notifying application services. Contributed by Willem Mulder. ([\#10107](https://github.com/matrix-org/synapse/issues/10107))
- Fix bug where the server would attempt to fetch the same history in the room from a remote server multiple times in parallel. ([\#10116](https://github.com/matrix-org/synapse/issues/10116))
- Fix a bug introduced in Synapse 1.33.0 which caused replication requests to fail when receiving a lot of very large events via federation. ([\#10118](https://github.com/matrix-org/synapse/issues/10118))
- Fix bug when using workers where pagination requests failed if a remote server returned zero events from `/backfill`. Introduced in 1.35.0. ([\#10133](https://github.com/matrix-org/synapse/issues/10133))


Improved Documentation
----------------------

- Clarify security note regarding hosting Synapse on the same domain as other web applications. ([\#9221](https://github.com/matrix-org/synapse/issues/9221))
- Update CAPTCHA documentation to mention turning off the verify origin feature. Contributed by @aaronraimist. ([\#10046](https://github.com/matrix-org/synapse/issues/10046))
- Tweak wording of database recommendation in `INSTALL.md`. Contributed by @aaronraimist. ([\#10057](https://github.com/matrix-org/synapse/issues/10057))
- Add initial infrastructure for rendering Synapse documentation with mdbook. ([\#10086](https://github.com/matrix-org/synapse/issues/10086))
- Convert the remaining Admin API documentation files to markdown. ([\#10089](https://github.com/matrix-org/synapse/issues/10089))
- Make a link in docs use HTTPS. Contributed by @RhnSharma. ([\#10130](https://github.com/matrix-org/synapse/issues/10130))
- Fix broken link in Docker docs. ([\#10132](https://github.com/matrix-org/synapse/issues/10132))


Deprecations and Removals
-------------------------

- Remove the experimental `spaces_enabled` flag. The spaces features are always available now. ([\#10063](https://github.com/matrix-org/synapse/issues/10063))


Internal Changes
----------------

- Tell CircleCI to build Docker images from `main` branch. ([\#9906](https://github.com/matrix-org/synapse/issues/9906))
- Simplify naming convention for release branches to only include the major and minor version numbers. ([\#10013](https://github.com/matrix-org/synapse/issues/10013))
- Add `parse_strings_from_args` for parsing an array from query parameters. ([\#10048](https://github.com/matrix-org/synapse/issues/10048), [\#10137](https://github.com/matrix-org/synapse/issues/10137))
- Remove some dead code regarding TLS certificate handling. ([\#10054](https://github.com/matrix-org/synapse/issues/10054))
- Remove redundant, unmaintained `convert_server_keys` script. ([\#10055](https://github.com/matrix-org/synapse/issues/10055))
- Improve the error message printed by synctl when synapse fails to start. ([\#10059](https://github.com/matrix-org/synapse/issues/10059))
- Fix GitHub Actions lint for newsfragments. ([\#10069](https://github.com/matrix-org/synapse/issues/10069))
- Update opentracing to inject the right context into the carrier. ([\#10074](https://github.com/matrix-org/synapse/issues/10074))
- Fix up `BatchingQueue` implementation. ([\#10078](https://github.com/matrix-org/synapse/issues/10078))
- Log method and path when dropping request due to size limit. ([\#10091](https://github.com/matrix-org/synapse/issues/10091))
- In Github Actions workflows, summarize the Sytest results in an easy-to-read format. ([\#10094](https://github.com/matrix-org/synapse/issues/10094))
- Make `/sync` do fewer state resolutions. ([\#10102](https://github.com/matrix-org/synapse/issues/10102))
- Add missing type hints to the admin API servlets. ([\#10105](https://github.com/matrix-org/synapse/issues/10105))
- Improve opentracing annotations for `Notifier`. ([\#10111](https://github.com/matrix-org/synapse/issues/10111))
- Enable Prometheus metrics for the jaeger client library. ([\#10112](https://github.com/matrix-org/synapse/issues/10112))
- Work to improve the responsiveness of `/sync` requests. ([\#10124](https://github.com/matrix-org/synapse/issues/10124))
- OpenTracing: use a consistent name for background processes. ([\#10135](https://github.com/matrix-org/synapse/issues/10135))


Synapse 1.35.1 (2021-06-03)
===========================

Bugfixes
--------

- Fix a bug introduced in v1.35.0 where invite-only rooms would be shown to all users in a space, regardless of if the user had access to it. ([\#10109](https://github.com/matrix-org/synapse/issues/10109))


Synapse 1.35.0 (2021-06-01)
===========================

Note that [the tag](https://github.com/matrix-org/synapse/releases/tag/v1.35.0rc3) and [docker images](https://hub.docker.com/layers/matrixdotorg/synapse/v1.35.0rc3/images/sha256-34ccc87bd99a17e2cbc0902e678b5937d16bdc1991ead097eee6096481ecf2c4?context=explore) for `v1.35.0rc3` were incorrectly built. If you are experiencing issues with either, it is recommended to upgrade to the equivalent tag or docker image for the `v1.35.0` release.

Deprecations and Removals
-------------------------

- The core Synapse development team plan to drop support for the [unstable API of MSC2858](https://github.com/matrix-org/matrix-doc/blob/master/proposals/2858-Multiple-SSO-Identity-Providers.md#unstable-prefix), including the undocumented `experimental.msc2858_enabled` config option, in August 2021. Client authors should ensure that their clients are updated to use the stable API (which has been supported since Synapse 1.30) well before that time, to give their users time to upgrade. ([\#10101](https://github.com/matrix-org/synapse/issues/10101))

Bugfixes
--------

- Fixed a bug causing replication requests to fail when receiving a lot of events via federation. Introduced in v1.33.0. ([\#10082](https://github.com/matrix-org/synapse/issues/10082))
- Fix HTTP response size limit to allow joining very large rooms over federation. Introduced in v1.33.0. ([\#10093](https://github.com/matrix-org/synapse/issues/10093))


Internal Changes
----------------

- Log method and path when dropping request due to size limit. ([\#10091](https://github.com/matrix-org/synapse/issues/10091))


Synapse 1.35.0rc2 (2021-05-27)
==============================

Bugfixes
--------

- Fix a bug introduced in v1.35.0rc1 when calling the spaces summary API via a GET request. ([\#10079](https://github.com/matrix-org/synapse/issues/10079))


Synapse 1.35.0rc1 (2021-05-25)
==============================

Features
--------

- Add experimental support to allow a user who could join a restricted room to view it in the spaces summary. ([\#9922](https://github.com/matrix-org/synapse/issues/9922), [\#10007](https://github.com/matrix-org/synapse/issues/10007), [\#10038](https://github.com/matrix-org/synapse/issues/10038))
- Reduce memory usage when joining very large rooms over federation. ([\#9958](https://github.com/matrix-org/synapse/issues/9958))
- Add a configuration option which allows enabling opentracing by user id. ([\#9978](https://github.com/matrix-org/synapse/issues/9978))
- Enable experimental support for [MSC2946](https://github.com/matrix-org/matrix-doc/pull/2946) (spaces summary API) and [MSC3083](https://github.com/matrix-org/matrix-doc/pull/3083) (restricted join rules) by default. ([\#10011](https://github.com/matrix-org/synapse/issues/10011))


Bugfixes
--------

- Fix a bug introduced in v1.26.0 which meant that `synapse_port_db` would not correctly initialise some postgres sequences, requiring manual updates afterwards. ([\#9991](https://github.com/matrix-org/synapse/issues/9991))
- Fix `synctl`'s `--no-daemonize` parameter to work correctly with worker processes. ([\#9995](https://github.com/matrix-org/synapse/issues/9995))
- Fix a validation bug introduced in v1.34.0 in the ordering of spaces in the space summary API. ([\#10002](https://github.com/matrix-org/synapse/issues/10002))
- Fixed deletion of new presence stream states from database. ([\#10014](https://github.com/matrix-org/synapse/issues/10014), [\#10033](https://github.com/matrix-org/synapse/issues/10033))
- Fixed a bug with very high resolution image uploads throwing internal server errors. ([\#10029](https://github.com/matrix-org/synapse/issues/10029))


Updates to the Docker image
---------------------------

- Fix bug introduced in Synapse 1.33.0 which caused a `Permission denied: '/homeserver.log'` error when starting Synapse with the generated log configuration. Contributed by Sergio Miguéns Iglesias. ([\#10045](https://github.com/matrix-org/synapse/issues/10045))


Improved Documentation
----------------------

- Add hardened systemd files as proposed in [#9760](https://github.com/matrix-org/synapse/issues/9760) and added them to `contrib/`. Change the docs to reflect the presence of these files. ([\#9803](https://github.com/matrix-org/synapse/issues/9803))
- Clarify documentation around SSO mapping providers generating unique IDs and localparts. ([\#9980](https://github.com/matrix-org/synapse/issues/9980))
- Updates to the PostgreSQL documentation (`postgres.md`). ([\#9988](https://github.com/matrix-org/synapse/issues/9988), [\#9989](https://github.com/matrix-org/synapse/issues/9989))
- Fix broken link in user directory documentation. Contributed by @junquera. ([\#10016](https://github.com/matrix-org/synapse/issues/10016))
- Add missing room state entry to the table of contents of room admin API. ([\#10043](https://github.com/matrix-org/synapse/issues/10043))


Deprecations and Removals
-------------------------

- Removed support for the deprecated `tls_fingerprints` configuration setting. Contributed by Jerin J Titus. ([\#9280](https://github.com/matrix-org/synapse/issues/9280))


Internal Changes
----------------

- Allow sending full presence to users via workers other than the one that called `ModuleApi.send_local_online_presence_to`. ([\#9823](https://github.com/matrix-org/synapse/issues/9823))
- Update comments in the space summary handler. ([\#9974](https://github.com/matrix-org/synapse/issues/9974))
- Minor enhancements to the `@cachedList` descriptor. ([\#9975](https://github.com/matrix-org/synapse/issues/9975))
- Split multipart email sending into a dedicated handler. ([\#9977](https://github.com/matrix-org/synapse/issues/9977))
- Run `black` on files in the `scripts` directory. ([\#9981](https://github.com/matrix-org/synapse/issues/9981))
- Add missing type hints to `synapse.util` module. ([\#9982](https://github.com/matrix-org/synapse/issues/9982))
- Simplify a few helper functions. ([\#9984](https://github.com/matrix-org/synapse/issues/9984), [\#9985](https://github.com/matrix-org/synapse/issues/9985), [\#9986](https://github.com/matrix-org/synapse/issues/9986))
- Remove unnecessary property from SQLBaseStore. ([\#9987](https://github.com/matrix-org/synapse/issues/9987))
- Remove `keylen` param on `LruCache`. ([\#9993](https://github.com/matrix-org/synapse/issues/9993))
- Update the Grafana dashboard in `contrib/`. ([\#10001](https://github.com/matrix-org/synapse/issues/10001))
- Add a batching queue implementation. ([\#10017](https://github.com/matrix-org/synapse/issues/10017))
- Reduce memory usage when verifying signatures on large numbers of events at once. ([\#10018](https://github.com/matrix-org/synapse/issues/10018))
- Properly invalidate caches for destination retry timings every (instead of expiring entries every 5 minutes). ([\#10036](https://github.com/matrix-org/synapse/issues/10036))
- Fix running complement tests with Synapse workers. ([\#10039](https://github.com/matrix-org/synapse/issues/10039))
- Fix typo in `get_state_ids_for_event` docstring where the return type was incorrect. ([\#10050](https://github.com/matrix-org/synapse/issues/10050))


Synapse 1.34.0 (2021-05-17)
===========================

This release deprecates the `room_invite_state_types` configuration setting. See the [upgrade notes](https://github.com/matrix-org/synapse/blob/release-v1.34.0/UPGRADE.rst#upgrading-to-v1340) for instructions on updating your configuration file to use the new `room_prejoin_state` setting.

This release also deprecates the `POST /_synapse/admin/v1/rooms/<room_id>/delete` admin API route. Server administrators are encouraged to update their scripts to use the new `DELETE /_synapse/admin/v1/rooms/<room_id>` route instead.


No significant changes since v1.34.0rc1.


Synapse 1.34.0rc1 (2021-05-12)
==============================

Features
--------

- Add experimental option to track memory usage of the caches. ([\#9881](https://github.com/matrix-org/synapse/issues/9881))
- Add support for `DELETE /_synapse/admin/v1/rooms/<room_id>`. ([\#9889](https://github.com/matrix-org/synapse/issues/9889))
- Add limits to how often Synapse will GC, ensuring that large servers do not end up GC thrashing if `gc_thresholds` has not been correctly set. ([\#9902](https://github.com/matrix-org/synapse/issues/9902))
- Improve performance of sending events for worker-based deployments using Redis. ([\#9905](https://github.com/matrix-org/synapse/issues/9905), [\#9950](https://github.com/matrix-org/synapse/issues/9950), [\#9951](https://github.com/matrix-org/synapse/issues/9951))
- Improve performance after joining a large room when presence is enabled. ([\#9910](https://github.com/matrix-org/synapse/issues/9910), [\#9916](https://github.com/matrix-org/synapse/issues/9916))
- Support stable identifiers for [MSC1772](https://github.com/matrix-org/matrix-doc/pull/1772) Spaces. `m.space.child` events will now be taken into account when populating the experimental spaces summary response. Please see [the upgrade notes](https://github.com/matrix-org/synapse/blob/release-v1.34.0/UPGRADE.rst#upgrading-to-v1340) if you have customised `room_invite_state_types` in your configuration. ([\#9915](https://github.com/matrix-org/synapse/issues/9915), [\#9966](https://github.com/matrix-org/synapse/issues/9966))
- Improve performance of backfilling in large rooms. ([\#9935](https://github.com/matrix-org/synapse/issues/9935))
- Add a config option to allow you to prevent device display names from being shared over federation. Contributed by @aaronraimist. ([\#9945](https://github.com/matrix-org/synapse/issues/9945))
- Update support for [MSC2946](https://github.com/matrix-org/matrix-doc/pull/2946): Spaces Summary. ([\#9947](https://github.com/matrix-org/synapse/issues/9947), [\#9954](https://github.com/matrix-org/synapse/issues/9954))


Bugfixes
--------

- Fix a bug introduced in v1.32.0 where the associated connection was improperly logged for SQL logging statements. ([\#9895](https://github.com/matrix-org/synapse/issues/9895))
- Correct the type hint for the `user_may_create_room_alias` method of spam checkers. It is provided a `RoomAlias`, not a `str`. ([\#9896](https://github.com/matrix-org/synapse/issues/9896))
- Fix bug where user directory could get out of sync if room visibility and membership changed in quick succession. ([\#9910](https://github.com/matrix-org/synapse/issues/9910))
- Include the `origin_server_ts` property in the experimental [MSC2946](https://github.com/matrix-org/matrix-doc/pull/2946) support to allow clients to properly sort rooms. ([\#9928](https://github.com/matrix-org/synapse/issues/9928))
- Fix bugs introduced in v1.23.0 which made the PostgreSQL port script fail when run with a newly-created SQLite database. ([\#9930](https://github.com/matrix-org/synapse/issues/9930))
- Fix a bug introduced in Synapse 1.29.0 which caused `m.room_key_request` to-device messages sent from one user to another to be dropped. ([\#9961](https://github.com/matrix-org/synapse/issues/9961), [\#9965](https://github.com/matrix-org/synapse/issues/9965))
- Fix a bug introduced in v1.27.0 preventing users and appservices exempt from ratelimiting from creating rooms with many invitees. ([\#9968](https://github.com/matrix-org/synapse/issues/9968))


Updates to the Docker image
---------------------------

- Add `startup_delay` to docker healthcheck to reduce waiting time for coming online and update the documentation with extra options. Contributed by @Maquis196. ([\#9913](https://github.com/matrix-org/synapse/issues/9913))


Improved Documentation
----------------------

- Add `port` argument to the Postgres database sample config section. ([\#9911](https://github.com/matrix-org/synapse/issues/9911))


Deprecations and Removals
-------------------------

- Mark as deprecated `POST /_synapse/admin/v1/rooms/<room_id>/delete`. ([\#9889](https://github.com/matrix-org/synapse/issues/9889))


Internal Changes
----------------

- Reduce the length of Synapse's access tokens. ([\#5588](https://github.com/matrix-org/synapse/issues/5588))
- Export jemalloc stats to Prometheus if it is being used. ([\#9882](https://github.com/matrix-org/synapse/issues/9882))
- Add type hints to presence handler. ([\#9885](https://github.com/matrix-org/synapse/issues/9885))
- Reduce memory usage of the LRU caches. ([\#9886](https://github.com/matrix-org/synapse/issues/9886))
- Add type hints to the `synapse.handlers` module. ([\#9896](https://github.com/matrix-org/synapse/issues/9896))
- Time response time for external cache requests. ([\#9904](https://github.com/matrix-org/synapse/issues/9904))
- Minor fixes to the `make_full_schema.sh` script. ([\#9931](https://github.com/matrix-org/synapse/issues/9931))
- Move database schema files into a common directory. ([\#9932](https://github.com/matrix-org/synapse/issues/9932))
- Add debug logging for lost/delayed to-device messages. ([\#9959](https://github.com/matrix-org/synapse/issues/9959))


Synapse 1.33.2 (2021-05-11)
===========================

Due to the security issue highlighted below, server administrators are encouraged to update Synapse. We are not aware of these vulnerabilities being exploited in the wild.

Security advisory
-----------------

This release fixes a denial of service attack ([CVE-2021-29471](https://github.com/matrix-org/synapse/security/advisories/GHSA-x345-32rc-8h85)) against Synapse's push rules implementation. Server admins are encouraged to upgrade.

Internal Changes
----------------

- Unpin attrs dependency. ([\#9946](https://github.com/matrix-org/synapse/issues/9946))


Synapse 1.33.1 (2021-05-06)
===========================

Bugfixes
--------

- Fix bug where `/sync` would break if using the latest version of `attrs` dependency, by pinning to a previous version. ([\#9937](https://github.com/matrix-org/synapse/issues/9937))


Synapse 1.33.0 (2021-05-05)
===========================

Features
--------

- Build Debian packages for Ubuntu 21.04 (Hirsute Hippo). ([\#9909](https://github.com/matrix-org/synapse/issues/9909))


Synapse 1.33.0rc2 (2021-04-29)
==============================

Bugfixes
--------

- Fix tight loop when handling presence replication when using workers. Introduced in v1.33.0rc1. ([\#9900](https://github.com/matrix-org/synapse/issues/9900))


Synapse 1.33.0rc1 (2021-04-28)
==============================

Features
--------

- Update experimental support for [MSC3083](https://github.com/matrix-org/matrix-doc/pull/3083): restricting room access via group membership. ([\#9800](https://github.com/matrix-org/synapse/issues/9800), [\#9814](https://github.com/matrix-org/synapse/issues/9814))
- Add experimental support for handling presence on a worker. ([\#9819](https://github.com/matrix-org/synapse/issues/9819), [\#9820](https://github.com/matrix-org/synapse/issues/9820), [\#9828](https://github.com/matrix-org/synapse/issues/9828), [\#9850](https://github.com/matrix-org/synapse/issues/9850))
- Return a new template when an user attempts to renew their account multiple times with the same token, stating that their account is set to expire. This replaces the invalid token template that would previously be shown in this case. This change concerns the optional account validity feature. ([\#9832](https://github.com/matrix-org/synapse/issues/9832))


Bugfixes
--------

- Fixes the OIDC SSO flow when using a `public_baseurl` value including a non-root URL path. ([\#9726](https://github.com/matrix-org/synapse/issues/9726))
- Fix thumbnail generation for some sites with non-standard content types. Contributed by @rkfg. ([\#9788](https://github.com/matrix-org/synapse/issues/9788))
- Add some sanity checks to identity server passed to 3PID bind/unbind endpoints. ([\#9802](https://github.com/matrix-org/synapse/issues/9802))
- Limit the size of HTTP responses read over federation. ([\#9833](https://github.com/matrix-org/synapse/issues/9833))
- Fix a bug which could cause Synapse to get stuck in a loop of resyncing device lists. ([\#9867](https://github.com/matrix-org/synapse/issues/9867))
- Fix a long-standing bug where errors from federation did not propagate to the client. ([\#9868](https://github.com/matrix-org/synapse/issues/9868))


Improved Documentation
----------------------

- Add a note to the docker docs mentioning that we mirror upstream's supported Docker platforms. ([\#9801](https://github.com/matrix-org/synapse/issues/9801))


Internal Changes
----------------

- Add a dockerfile for running Synapse in worker-mode under Complement. ([\#9162](https://github.com/matrix-org/synapse/issues/9162))
- Apply `pyupgrade` across the codebase. ([\#9786](https://github.com/matrix-org/synapse/issues/9786))