CHANGES.md

Synapse 1.12.1 (2020-04-02)
===========================

No significant changes since 1.12.1rc1.


Synapse 1.12.1rc1 (2020-03-31)
==============================

Bugfixes
--------

- Fix starting workers when federation sending not split out. ([\#7133](https://github.com/matrix-org/synapse/issues/7133)). Introduced in v1.12.0.
- Avoid importing `sqlite3` when using the postgres backend. Contributed by David Vo. ([\#7155](https://github.com/matrix-org/synapse/issues/7155)). Introduced in v1.12.0rc1.
- Fix a bug which could cause outbound federation traffic to stop working if a client uploaded an incorrect e2e device signature. ([\#7177](https://github.com/matrix-org/synapse/issues/7177)). Introduced in v1.11.0.

Synapse 1.12.0 (2020-03-23)
===========================

Debian packages and Docker images are rebuilt using the latest versions of
dependency libraries, including Twisted 20.3.0. **Please see security advisory
below**.

Potential slow database update during upgrade
---------------------------------------------

Synapse 1.12.0 includes a database update which is run as part of the upgrade,
and which may take some time (several hours in the case of a large
server). Synapse will not respond to HTTP requests while this update is taking
place. For imformation on seeing if you are affected, and workaround if you
are, see the [upgrade notes](docs/upgrade.md#upgrading-to-v1120).

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

Synapse may be vulnerable to request-smuggling attacks when it is used with a
reverse-proxy. The vulnerabilties are fixed in Twisted 20.3.0, and are
described in
[CVE-2020-10108](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-10108)
and
[CVE-2020-10109](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-10109).
For a good introduction to this class of request-smuggling attacks, see
https://portswigger.net/research/http-desync-attacks-request-smuggling-reborn.

We are not aware of these vulnerabilities being exploited in the wild, and
do not believe that they are exploitable with current versions of any reverse
proxies. Nevertheless, we recommend that all Synapse administrators ensure that
they have the latest versions of the Twisted library to ensure that their
installation remains secure.

* Administrators using the [`matrix.org` Docker
  image](https://hub.docker.com/r/matrixdotorg/synapse/) or the [Debian/Ubuntu
  packages from
  `matrix.org`](https://matrix-org.github.io/synapse/latest/setup/installation.html#matrixorg-packages)
  should ensure that they have version 1.12.0 installed: these images include
  Twisted 20.3.0.
* Administrators who have [installed Synapse from
  source](https://matrix-org.github.io/synapse/latest/setup/installation.html#installing-from-source)
  should upgrade Twisted within their virtualenv by running:
  ```sh
  <path_to_virtualenv>/bin/pip install 'Twisted>=20.3.0'
  ```
* Administrators who have installed Synapse from distribution packages should
  consult the information from their distributions.

The `matrix.org` Synapse instance was not vulnerable to these vulnerabilities.

Advance notice of change to the default `git` branch for Synapse
----------------------------------------------------------------

Currently, the default `git` branch for Synapse is `master`, which tracks the
latest release.

After the release of Synapse 1.13.0, we intend to change this default to
`develop`, which is the development tip. This is more consistent with common
practice and modern `git` usage.

Although we try to keep `develop` in a stable state, there may be occasions
where regressions creep in. Developers and distributors who have scripts which
run builds using the default branch of `Synapse` should therefore consider
pinning their scripts to `master`.


Synapse 1.12.0rc1 (2020-03-19)
==============================

Features
--------

- Changes related to room alias management ([MSC2432](https://github.com/matrix-org/matrix-doc/pull/2432)):
  - Publishing/removing a room from the room directory now requires the user to have a power level capable of modifying the canonical alias, instead of the room aliases. ([\#6965](https://github.com/matrix-org/synapse/issues/6965))
  - Validate the `alt_aliases` property of canonical alias events. ([\#6971](https://github.com/matrix-org/synapse/issues/6971))
  - Users with a power level sufficient to modify the canonical alias of a room can now delete room aliases. ([\#6986](https://github.com/matrix-org/synapse/issues/6986))
  - Implement updated authorization rules and redaction rules for aliases events, from [MSC2261](https://github.com/matrix-org/matrix-doc/pull/2261) and [MSC2432](https://github.com/matrix-org/matrix-doc/pull/2432). ([\#7037](https://github.com/matrix-org/synapse/issues/7037))
  - Stop sending m.room.aliases events during room creation and upgrade. ([\#6941](https://github.com/matrix-org/synapse/issues/6941))
  - Synapse no longer uses room alias events to calculate room names for push notifications. ([\#6966](https://github.com/matrix-org/synapse/issues/6966))
  - The room list endpoint no longer returns a list of aliases. ([\#6970](https://github.com/matrix-org/synapse/issues/6970))
  - Remove special handling of aliases events from [MSC2260](https://github.com/matrix-org/matrix-doc/pull/2260) added in v1.10.0rc1. ([\#7034](https://github.com/matrix-org/synapse/issues/7034))
- Expose the `synctl`, `hash_password` and `generate_config` commands in the snapcraft package. Contributed by @devec0. ([\#6315](https://github.com/matrix-org/synapse/issues/6315))
- Check that server_name is correctly set before running database updates. ([\#6982](https://github.com/matrix-org/synapse/issues/6982))
- Break down monthly active users by `appservice_id` and emit via Prometheus. ([\#7030](https://github.com/matrix-org/synapse/issues/7030))
- Render a configurable and comprehensible error page if something goes wrong during the SAML2 authentication process. ([\#7058](https://github.com/matrix-org/synapse/issues/7058), [\#7067](https://github.com/matrix-org/synapse/issues/7067))
- Add an optional parameter to control whether other sessions are logged out when a user's password is modified. ([\#7085](https://github.com/matrix-org/synapse/issues/7085))
- Add prometheus metrics for the number of active pushers. ([\#7103](https://github.com/matrix-org/synapse/issues/7103), [\#7106](https://github.com/matrix-org/synapse/issues/7106))
- Improve performance when making HTTPS requests to sygnal, sydent, etc, by sharing the SSL context object between connections. ([\#7094](https://github.com/matrix-org/synapse/issues/7094))


Bugfixes
--------

- When a user's profile is updated via the admin API, also generate a displayname/avatar update for that user in each room. ([\#6572](https://github.com/matrix-org/synapse/issues/6572))
- Fix a couple of bugs in email configuration handling. ([\#6962](https://github.com/matrix-org/synapse/issues/6962))
- Fix an issue affecting worker-based deployments where replication would stop working, necessitating a full restart, after joining a large room. ([\#6967](https://github.com/matrix-org/synapse/issues/6967))
- Fix `duplicate key` error which was logged when rejoining a room over federation. ([\#6968](https://github.com/matrix-org/synapse/issues/6968))
- Prevent user from setting 'deactivated' to anything other than a bool on the v2 PUT /users Admin API. ([\#6990](https://github.com/matrix-org/synapse/issues/6990))
- Fix py35-old CI by using native tox package. ([\#7018](https://github.com/matrix-org/synapse/issues/7018))
- Fix a bug causing `org.matrix.dummy_event` to be included in responses from `/sync`. ([\#7035](https://github.com/matrix-org/synapse/issues/7035))
- Fix a bug that renders UTF-8 text files incorrectly when loaded from media. Contributed by @TheStranjer. ([\#7044](https://github.com/matrix-org/synapse/issues/7044))
- Fix a bug that would cause Synapse to respond with an error about event visibility if a client tried to request the state of a room at a given token. ([\#7066](https://github.com/matrix-org/synapse/issues/7066))
- Repair a data-corruption issue which was introduced in Synapse 1.10, and fixed in Synapse 1.11, and which could cause `/sync` to return with 404 errors about missing events and unknown rooms. ([\#7070](https://github.com/matrix-org/synapse/issues/7070))
- Fix a bug causing account validity renewal emails to be sent even if the feature is turned off in some cases. ([\#7074](https://github.com/matrix-org/synapse/issues/7074))


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

- Updated CentOS8 install instructions. Contributed by Richard Kellner. ([\#6925](https://github.com/matrix-org/synapse/issues/6925))
- Fix `POSTGRES_INITDB_ARGS` in the `contrib/docker/docker-compose.yml` example docker-compose configuration. ([\#6984](https://github.com/matrix-org/synapse/issues/6984))
- Change date in [INSTALL.md](./INSTALL.md#tls-certificates) for last date of getting TLS certificates to November 2019. ([\#7015](https://github.com/matrix-org/synapse/issues/7015))
- Document that the fallback auth endpoints must be routed to the same worker node as the register endpoints. ([\#7048](https://github.com/matrix-org/synapse/issues/7048))


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

- Remove the unused query_auth federation endpoint per [MSC2451](https://github.com/matrix-org/matrix-doc/pull/2451). ([\#7026](https://github.com/matrix-org/synapse/issues/7026))


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

- Add type hints to `logging/context.py`. ([\#6309](https://github.com/matrix-org/synapse/issues/6309))
- Add some clarifications to `README.md` in the database schema directory. ([\#6615](https://github.com/matrix-org/synapse/issues/6615))
- Refactoring work in preparation for changing the event redaction algorithm. ([\#6874](https://github.com/matrix-org/synapse/issues/6874), [\#6875](https://github.com/matrix-org/synapse/issues/6875), [\#6983](https://github.com/matrix-org/synapse/issues/6983), [\#7003](https://github.com/matrix-org/synapse/issues/7003))
- Improve performance of v2 state resolution for large rooms. ([\#6952](https://github.com/matrix-org/synapse/issues/6952), [\#7095](https://github.com/matrix-org/synapse/issues/7095))
- Reduce time spent doing GC, by freezing objects on startup. ([\#6953](https://github.com/matrix-org/synapse/issues/6953))
- Minor perfermance fixes to `get_auth_chain_ids`. ([\#6954](https://github.com/matrix-org/synapse/issues/6954))
- Don't record remote cross-signing keys in the `devices` table. ([\#6956](https://github.com/matrix-org/synapse/issues/6956))
- Use flake8-comprehensions to enforce good hygiene of list/set/dict comprehensions. ([\#6957](https://github.com/matrix-org/synapse/issues/6957))
- Merge worker apps together. ([\#6964](https://github.com/matrix-org/synapse/issues/6964), [\#7002](https://github.com/matrix-org/synapse/issues/7002), [\#7055](https://github.com/matrix-org/synapse/issues/7055), [\#7104](https://github.com/matrix-org/synapse/issues/7104))
- Remove redundant `store_room` call from `FederationHandler._process_received_pdu`. ([\#6979](https://github.com/matrix-org/synapse/issues/6979))
- Update warning for incorrect database collation/ctype to include link to documentation. ([\#6985](https://github.com/matrix-org/synapse/issues/6985))
- Add some type annotations to the database storage classes. ([\#6987](https://github.com/matrix-org/synapse/issues/6987))
- Port `synapse.handlers.presence` to async/await. ([\#6991](https://github.com/matrix-org/synapse/issues/6991), [\#7019](https://github.com/matrix-org/synapse/issues/7019))
- Add some type annotations to the federation base & client classes. ([\#6995](https://github.com/matrix-org/synapse/issues/6995))
- Port `synapse.rest.keys` to async/await. ([\#7020](https://github.com/matrix-org/synapse/issues/7020))
- Add a type check to `is_verified` when processing room keys. ([\#7045](https://github.com/matrix-org/synapse/issues/7045))
- Add type annotations and comments to the auth handler. ([\#7063](https://github.com/matrix-org/synapse/issues/7063))


Synapse 1.11.1 (2020-03-03)
===========================

This release includes a security fix impacting installations using Single Sign-On (i.e. SAML2 or CAS) for authentication. Administrators of such installations are encouraged to upgrade as soon as possible.

The release also includes fixes for a couple of other bugs.

Bugfixes
--------

- Add a confirmation step to the SSO login flow before redirecting users to the redirect URL. ([b2bd54a2](https://github.com/matrix-org/synapse/commit/b2bd54a2e31d9a248f73fadb184ae9b4cbdb49f9), [65c73cdf](https://github.com/matrix-org/synapse/commit/65c73cdfec1876a9fec2fd2c3a74923cd146fe0b), [a0178df1](https://github.com/matrix-org/synapse/commit/a0178df10422a76fd403b82d2b2a4ed28a9a9d1e))
- Fixed set a user as an admin with the admin API `PUT /_synapse/admin/v2/users/<user_id>`. Contributed by @dklimpel. ([\#6910](https://github.com/matrix-org/synapse/issues/6910))
- Fix bug introduced in Synapse 1.11.0 which sometimes caused errors when joining rooms over federation, with `'coroutine' object has no attribute 'event_id'`. ([\#6996](https://github.com/matrix-org/synapse/issues/6996))


Synapse 1.11.0 (2020-02-21)
===========================

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

- Small grammatical fixes to the ACME v1 deprecation notice. ([\#6944](https://github.com/matrix-org/synapse/issues/6944))


Synapse 1.11.0rc1 (2020-02-19)
==============================

Features
--------

- Admin API to add or modify threepids of user accounts. ([\#6769](https://github.com/matrix-org/synapse/issues/6769))
- Limit the number of events that can be requested by the backfill federation API to 100. ([\#6864](https://github.com/matrix-org/synapse/issues/6864))
- Add ability to run some group APIs on workers. ([\#6866](https://github.com/matrix-org/synapse/issues/6866))
- Reject device display names over 100 characters in length to prevent abuse. ([\#6882](https://github.com/matrix-org/synapse/issues/6882))
- Add ability to route federation user device queries to workers. ([\#6873](https://github.com/matrix-org/synapse/issues/6873))
- The result of a user directory search can now be filtered via the spam checker. ([\#6888](https://github.com/matrix-org/synapse/issues/6888))
- Implement new `GET /_matrix/client/unstable/org.matrix.msc2432/rooms/{roomId}/aliases` endpoint as per [MSC2432](https://github.com/matrix-org/matrix-doc/pull/2432). ([\#6939](https://github.com/matrix-org/synapse/issues/6939), [\#6948](https://github.com/matrix-org/synapse/issues/6948), [\#6949](https://github.com/matrix-org/synapse/issues/6949))
- Stop sending `m.room.alias` events wheng adding / removing aliases. Check `alt_aliases` in the latest `m.room.canonical_alias` event when deleting an alias. ([\#6904](https://github.com/matrix-org/synapse/issues/6904))
- Change the default power levels of invites, tombstones and server ACLs for new rooms. ([\#6834](https://github.com/matrix-org/synapse/issues/6834))

Bugfixes
--------

- Fixed third party event rules function `on_create_room`'s return value being ignored. ([\#6781](https://github.com/matrix-org/synapse/issues/6781))
- Allow URL-encoded User IDs on `/_synapse/admin/v2/users/<user_id>[/admin]` endpoints. Thanks to @NHAS for reporting. ([\#6825](https://github.com/matrix-org/synapse/issues/6825))
- Fix Synapse refusing to start if `federation_certificate_verification_whitelist` option is blank. ([\#6849](https://github.com/matrix-org/synapse/issues/6849))
- Fix errors from logging in the purge jobs related to the message retention policies support. ([\#6945](https://github.com/matrix-org/synapse/issues/6945))
- Return a 404 instead of 200 for querying information of a non-existant user through the admin API. ([\#6901](https://github.com/matrix-org/synapse/issues/6901))


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

- The deprecated "generate-config-on-the-fly" mode is no longer supported. ([\#6918](https://github.com/matrix-org/synapse/issues/6918))


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

- Add details of PR merge strategy to contributing docs. ([\#6846](https://github.com/matrix-org/synapse/issues/6846))
- Spell out that the last event sent to a room won't be deleted by a purge. ([\#6891](https://github.com/matrix-org/synapse/issues/6891))
- Update Synapse's documentation to warn about the deprecation of ACME v1. ([\#6905](https://github.com/matrix-org/synapse/issues/6905), [\#6907](https://github.com/matrix-org/synapse/issues/6907), [\#6909](https://github.com/matrix-org/synapse/issues/6909))
- Add documentation for the spam checker. ([\#6906](https://github.com/matrix-org/synapse/issues/6906))
- Fix worker docs to point `/publicised_groups` API correctly. ([\#6938](https://github.com/matrix-org/synapse/issues/6938))
- Clean up and update docs on setting up federation. ([\#6940](https://github.com/matrix-org/synapse/issues/6940))
- Add a warning about indentation to generated configuration files. ([\#6920](https://github.com/matrix-org/synapse/issues/6920))
- Databases created using the compose file in contrib/docker will now always have correct encoding and locale settings. Contributed by Fridtjof Mund. ([\#6921](https://github.com/matrix-org/synapse/issues/6921))
- Update pip install directions in readme to avoid error when using zsh. ([\#6855](https://github.com/matrix-org/synapse/issues/6855))


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

- Remove `m.lazy_load_members` from `unstable_features` since lazy loading is in the stable Client-Server API version r0.5.0. ([\#6877](https://github.com/matrix-org/synapse/issues/6877))


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

- Add type hints to `SyncHandler`. ([\#6821](https://github.com/matrix-org/synapse/issues/6821))
- Refactoring work in preparation for changing the event redaction algorithm. ([\#6823](https://github.com/matrix-org/synapse/issues/6823), [\#6827](https://github.com/matrix-org/synapse/issues/6827), [\#6854](https://github.com/matrix-org/synapse/issues/6854), [\#6856](https://github.com/matrix-org/synapse/issues/6856), [\#6857](https://github.com/matrix-org/synapse/issues/6857), [\#6858](https://github.com/matrix-org/synapse/issues/6858))
- Fix stacktraces when using `ObservableDeferred` and async/await. ([\#6836](https://github.com/matrix-org/synapse/issues/6836))
- Port much of `synapse.handlers.federation` to async/await. ([\#6837](https://github.com/matrix-org/synapse/issues/6837), [\#6840](https://github.com/matrix-org/synapse/issues/6840))
- Populate `rooms.room_version` database column at startup, rather than in a background update. ([\#6847](https://github.com/matrix-org/synapse/issues/6847))
- Reduce amount we log at `INFO` level. ([\#6833](https://github.com/matrix-org/synapse/issues/6833), [\#6862](https://github.com/matrix-org/synapse/issues/6862))
- Remove unused `get_room_stats_state` method. ([\#6869](https://github.com/matrix-org/synapse/issues/6869))
- Add typing to `synapse.federation.sender` and port to async/await. ([\#6871](https://github.com/matrix-org/synapse/issues/6871))
- Refactor `_EventInternalMetadata` object to improve type safety. ([\#6872](https://github.com/matrix-org/synapse/issues/6872))
- Add an additional entry to the SyTest blacklist for worker mode. ([\#6883](https://github.com/matrix-org/synapse/issues/6883))
- Fix the use of sed in the linting scripts when using BSD sed. ([\#6887](https://github.com/matrix-org/synapse/issues/6887))
- Add type hints to the spam checker module. ([\#6915](https://github.com/matrix-org/synapse/issues/6915))
- Convert the directory handler tests to use HomeserverTestCase. ([\#6919](https://github.com/matrix-org/synapse/issues/6919))
- Increase DB/CPU perf of `_is_server_still_joined` check. ([\#6936](https://github.com/matrix-org/synapse/issues/6936))
- Tiny optimisation for incoming HTTP request dispatch. ([\#6950](https://github.com/matrix-org/synapse/issues/6950))


Synapse 1.10.1 (2020-02-17)
===========================

Bugfixes
--------

- Fix a bug introduced in Synapse 1.10.0 which would cause room state to be cleared in the database if Synapse was upgraded direct from 1.2.1 or earlier to 1.10.0. ([\#6924](https://github.com/matrix-org/synapse/issues/6924))


Synapse 1.10.0 (2020-02-12)
===========================

**WARNING to client developers**: As of this release Synapse validates `client_secret` parameters in the Client-Server API as per the spec. See [\#6766](https://github.com/matrix-org/synapse/issues/6766) for details.

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

- Update the docker images to Alpine Linux 3.11. ([\#6897](https://github.com/matrix-org/synapse/issues/6897))


Synapse 1.10.0rc5 (2020-02-11)
==============================

Bugfixes
--------

- Fix the filtering introduced in 1.10.0rc3 to also apply to the state blocks returned by `/sync`. ([\#6884](https://github.com/matrix-org/synapse/issues/6884))

Synapse 1.10.0rc4 (2020-02-11)
==============================

This release candidate was built incorrectly and is superceded by 1.10.0rc5.

Synapse 1.10.0rc3 (2020-02-10)
==============================

Features
--------

- Filter out `m.room.aliases` from the CS API to mitigate abuse while a better solution is specced. ([\#6878](https://github.com/matrix-org/synapse/issues/6878))


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

- Fix continuous integration failures with old versions of `pip`, which were introduced by a release of the `zipp` library. ([\#6880](https://github.com/matrix-org/synapse/issues/6880))


Synapse 1.10.0rc2 (2020-02-06)
==============================

Bugfixes
--------

- Fix an issue with cross-signing where device signatures were not sent to remote servers. ([\#6844](https://github.com/matrix-org/synapse/issues/6844))
- Fix to the unknown remote device detection which was introduced in 1.10.rc1. ([\#6848](https://github.com/matrix-org/synapse/issues/6848))


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

- Detect unexpected sender keys on remote encrypted events and resync device lists. ([\#6850](https://github.com/matrix-org/synapse/issues/6850))


Synapse 1.10.0rc1 (2020-01-31)
==============================

Features
--------

- Add experimental support for updated authorization rules for aliases events, from [MSC2260](https://github.com/matrix-org/matrix-doc/pull/2260). ([\#6787](https://github.com/matrix-org/synapse/issues/6787), [\#6790](https://github.com/matrix-org/synapse/issues/6790), [\#6794](https://github.com/matrix-org/synapse/issues/6794))


Bugfixes
--------

- Warn if postgres database has a non-C locale, as that can cause issues when upgrading locales (e.g. due to upgrading OS). ([\#6734](https://github.com/matrix-org/synapse/issues/6734))
- Minor fixes to `PUT /_synapse/admin/v2/users` admin api. ([\#6761](https://github.com/matrix-org/synapse/issues/6761))
- Validate `client_secret` parameter using the regex provided by the Client-Server API, temporarily allowing `:` characters for older clients. The `:` character will be removed in a future release. ([\#6767](https://github.com/matrix-org/synapse/issues/6767))
- Fix persisting redaction events that have been redacted (or otherwise don't have a redacts key). ([\#6771](https://github.com/matrix-org/synapse/issues/6771))
- Fix outbound federation request metrics. ([\#6795](https://github.com/matrix-org/synapse/issues/6795))
- Fix bug where querying a remote user's device keys that weren't cached resulted in only returning a single device. ([\#6796](https://github.com/matrix-org/synapse/issues/6796))
- Fix race in federation sender worker that delayed sending of device updates. ([\#6799](https://github.com/matrix-org/synapse/issues/6799), [\#6800](https://github.com/matrix-org/synapse/issues/6800))
- Fix bug where Synapse didn't invalidate cache of remote users' devices when Synapse left a room. ([\#6801](https://github.com/matrix-org/synapse/issues/6801))
- Fix waking up other workers when remote server is detected to have come back online. ([\#6811](https://github.com/matrix-org/synapse/issues/6811))


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

- Clarify documentation related to `user_dir` and `federation_reader` workers. ([\#6775](https://github.com/matrix-org/synapse/issues/6775))


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

- Record room versions in the `rooms` table. ([\#6729](https://github.com/matrix-org/synapse/issues/6729), [\#6788](https://github.com/matrix-org/synapse/issues/6788), [\#6810](https://github.com/matrix-org/synapse/issues/6810))
- Propagate cache invalidates from workers to other workers. ([\#6748](https://github.com/matrix-org/synapse/issues/6748))
- Remove some unnecessary admin handler abstraction methods. ([\#6751](https://github.com/matrix-org/synapse/issues/6751))
- Add some debugging for media storage providers. ([\#6757](https://github.com/matrix-org/synapse/issues/6757))
- Detect unknown remote devices and mark cache as stale. ([\#6776](https://github.com/matrix-org/synapse/issues/6776), [\#6819](https://github.com/matrix-org/synapse/issues/6819))
- Attempt to resync remote users' devices when detected as stale. ([\#6786](https://github.com/matrix-org/synapse/issues/6786))
- Delete current state from the database when server leaves a room. ([\#6792](https://github.com/matrix-org/synapse/issues/6792))
- When a client asks for a remote user's device keys check if the local cache for that user has been marked as potentially stale. ([\#6797](https://github.com/matrix-org/synapse/issues/6797))
- Add background update to clean out left rooms from current state. ([\#6802](https://github.com/matrix-org/synapse/issues/6802), [\#6816](https://github.com/matrix-org/synapse/issues/6816))
- Refactoring work in preparation for changing the event redaction algorithm. ([\#6803](https://github.com/matrix-org/synapse/issues/6803), [\#6805](https://github.com/matrix-org/synapse/issues/6805), [\#6806](https://github.com/matrix-org/synapse/issues/6806), [\#6807](https://github.com/matrix-org/synapse/issues/6807), [\#6820](https://github.com/matrix-org/synapse/issues/6820))


Synapse 1.9.1 (2020-01-28)
==========================

Bugfixes
--------

- Fix bug where setting `mau_limit_reserved_threepids` config would cause Synapse to refuse to start. ([\#6793](https://github.com/matrix-org/synapse/issues/6793))


Synapse 1.9.0 (2020-01-23)
==========================

**WARNING**: As of this release, Synapse no longer supports versions of SQLite before 3.11, and will refuse to start when configured to use an older version. Administrators are recommended to migrate their database to Postgres (see instructions [here](docs/postgres.md)).

If your Synapse deployment uses workers, note that the reverse-proxy configurations for the `synapse.app.media_repository`, `synapse.app.federation_reader` and `synapse.app.event_creator` workers have changed, with the addition of a few paths (see the updated configurations [here](docs/workers.md#available-worker-applications)). Existing configurations will continue to work.


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

- Fix endpoint documentation for the List Rooms admin API. ([\#6770](https://github.com/matrix-org/synapse/issues/6770))


Synapse 1.9.0rc1 (2020-01-22)
=============================

Features
--------

- Allow admin to create or modify a user. Contributed by Awesome Technologies Innovationslabor GmbH. ([\#5742](https://github.com/matrix-org/synapse/issues/5742))
- Add new quarantine media admin APIs to quarantine by media ID or by user who uploaded the media. ([\#6681](https://github.com/matrix-org/synapse/issues/6681), [\#6756](https://github.com/matrix-org/synapse/issues/6756))
- Add `org.matrix.e2e_cross_signing` to `unstable_features` in `/versions` as per [MSC1756](https://github.com/matrix-org/matrix-doc/pull/1756). ([\#6712](https://github.com/matrix-org/synapse/issues/6712))
- Add a new admin API to list and filter rooms on the server. ([\#6720](https://github.com/matrix-org/synapse/issues/6720))


Bugfixes
--------

- Correctly proxy HTTP errors due to API calls to remote group servers. ([\#6654](https://github.com/matrix-org/synapse/issues/6654))
- Fix media repo admin APIs when using a media worker. ([\#6664](https://github.com/matrix-org/synapse/issues/6664))
- Fix "CRITICAL" errors being logged when a request is received for a uri containing non-ascii characters. ([\#6682](https://github.com/matrix-org/synapse/issues/6682))
- Fix a bug where we would assign a numeric user ID if somebody tried registering with an empty username. ([\#6690](https://github.com/matrix-org/synapse/issues/6690))
- Fix `purge_room` admin API. ([\#6711](https://github.com/matrix-org/synapse/issues/6711))
- Fix a bug causing Synapse to not always purge quiet rooms with a low `max_lifetime` in their message retention policies when running the automated purge jobs. ([\#6714](https://github.com/matrix-org/synapse/issues/6714))
- Fix the `synapse_port_db` not correctly running background updates. Thanks @tadzik for reporting. ([\#6718](https://github.com/matrix-org/synapse/issues/6718))
- Fix changing password via user admin API. ([\#6730](https://github.com/matrix-org/synapse/issues/6730))
- Fix `/events/:event_id` deprecated API. ([\#6731](https://github.com/matrix-org/synapse/issues/6731))
- Fix monthly active user limiting support for worker mode, fixes [#4639](https://github.com/matrix-org/synapse/issues/4639). ([\#6742](https://github.com/matrix-org/synapse/issues/6742))
- Fix bug when setting `account_validity` to an empty block in the config. Thanks to @Sorunome for reporting. ([\#6747](https://github.com/matrix-org/synapse/issues/6747))
- Fix `AttributeError: 'NoneType' object has no attribute 'get'` in `hash_password` when configuration has an empty `password_config`. Contributed by @ivilata. ([\#6753](https://github.com/matrix-org/synapse/issues/6753))
- Fix the `docker-compose.yaml` overriding the entire `/etc` folder of the container. Contributed by Fabian Meyer. ([\#6656](https://github.com/matrix-org/synapse/issues/6656))


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

- Fix a typo in the configuration example for purge jobs in the sample configuration file. ([\#6621](https://github.com/matrix-org/synapse/issues/6621))
- Add complete documentation of the message retention policies support. ([\#6624](https://github.com/matrix-org/synapse/issues/6624), [\#6665](https://github.com/matrix-org/synapse/issues/6665))
- Add some helpful tips about changelog entries to the GitHub pull request template. ([\#6663](https://github.com/matrix-org/synapse/issues/6663))
- Clarify the `account_validity` and `email` sections of the sample configuration. ([\#6685](https://github.com/matrix-org/synapse/issues/6685))
- Add more endpoints to the documentation for Synapse workers. ([\#6698](https://github.com/matrix-org/synapse/issues/6698))


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

- Synapse no longer supports versions of SQLite before 3.11, and will refuse to start when configured to use an older version. Administrators are recommended to migrate their database to Postgres (see instructions [here](docs/postgres.md)). ([\#6675](https://github.com/matrix-org/synapse/issues/6675))


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

- Add `local_current_membership` table for tracking local user membership state in rooms. ([\#6655](https://github.com/matrix-org/synapse/issues/6655), [\#6728](https://github.com/matrix-org/synapse/issues/6728))
- Port `synapse.replication.tcp` to async/await. ([\#6666](https://github.com/matrix-org/synapse/issues/6666))
- Fixup `synapse.replication` to pass mypy checks. ([\#6667](https://github.com/matrix-org/synapse/issues/6667))
- Allow `additional_resources` to implement `IResource` directly. ([\#6686](https://github.com/matrix-org/synapse/issues/6686))
- Allow REST endpoint implementations to raise a `RedirectException`, which will redirect the user's browser to a given location. ([\#6687](https://github.com/matrix-org/synapse/issues/6687))
- Updates and extensions to the module API. ([\#6688](https://github.com/matrix-org/synapse/issues/6688))
- Updates to the SAML mapping provider API. ([\#6689](https://github.com/matrix-org/synapse/issues/6689), [\#6723](https://github.com/matrix-org/synapse/issues/6723))
- Remove redundant `RegistrationError` class. ([\#6691](https://github.com/matrix-org/synapse/issues/6691))
- Don't block processing of incoming EDUs behind processing PDUs in the same transaction. ([\#6697](https://github.com/matrix-org/synapse/issues/6697))
- Remove duplicate check for the `session` query parameter on the `/auth/xxx/fallback/web` Client-Server endpoint. ([\#6702](https://github.com/matrix-org/synapse/issues/6702))
- Attempt to retry sending a transaction when we detect a remote server has come back online, rather than waiting for a transaction to be triggered by new data. ([\#6706](https://github.com/matrix-org/synapse/issues/6706))
- Add `StateMap` type alias to simplify types. ([\#6715](https://github.com/matrix-org/synapse/issues/6715))
- Add a `DeltaState` to track changes to be made to current state during event persistence. ([\#6716](https://github.com/matrix-org/synapse/issues/6716))
- Add more logging around message retention policies support. ([\#6717](https://github.com/matrix-org/synapse/issues/6717))
- When processing a SAML response, log the assertions for easier configuration. ([\#6724](https://github.com/matrix-org/synapse/issues/6724))
- Fixup `synapse.rest` to pass mypy. ([\#6732](https://github.com/matrix-org/synapse/issues/6732), [\#6764](https://github.com/matrix-org/synapse/issues/6764))
- Fixup `synapse.api` to pass mypy. ([\#6733](https://github.com/matrix-org/synapse/issues/6733))
- Allow streaming cache 'invalidate all' to workers. ([\#6749](https://github.com/matrix-org/synapse/issues/6749))
- Remove unused CI docker compose files. ([\#6754](https://github.com/matrix-org/synapse/issues/6754))


Synapse 1.8.0 (2020-01-09)
==========================

**WARNING**: As of this release Synapse will refuse to start if the `log_file` config option is specified. Support for the option was removed in v1.3.0.


Bugfixes
--------

- Fix `GET` request on `/_synapse/admin/v2/users` endpoint. Contributed by Awesome Technologies Innovationslabor GmbH. ([\#6563](https://github.com/matrix-org/synapse/issues/6563))
- Fix incorrect signing of responses from the key server implementation. ([\#6657](https://github.com/matrix-org/synapse/issues/6657))


Synapse 1.8.0rc1 (2020-01-07)
=============================

Features
--------

- Add v2 APIs for the `send_join` and `send_leave` federation endpoints (as described in [MSC1802](https://github.com/matrix-org/matrix-doc/pull/1802)). ([\#6349](https://github.com/matrix-org/synapse/issues/6349))
- Add a develop script to generate full SQL schemas. ([\#6394](https://github.com/matrix-org/synapse/issues/6394))
- Add custom SAML username mapping functionality through an external provider plugin. ([\#6411](https://github.com/matrix-org/synapse/issues/6411))
- Automatically delete empty groups/communities. ([\#6453](https://github.com/matrix-org/synapse/issues/6453))
- Add option `limit_profile_requests_to_users_who_share_rooms` to prevent requirement of a local user sharing a room with another user to query their profile information. ([\#6523](https://github.com/matrix-org/synapse/issues/6523))
- Add an `export_signing_key` script to extract the public part of signing keys when rotating them. ([\#6546](https://github.com/matrix-org/synapse/issues/6546))
- Add experimental config option to specify multiple databases. ([\#6580](https://github.com/matrix-org/synapse/issues/6580))
- Raise an error if someone tries to use the `log_file` config option. ([\#6626](https://github.com/matrix-org/synapse/issues/6626))


Bugfixes
--------

- Prevent redacted events from being returned during message search. ([\#6377](https://github.com/matrix-org/synapse/issues/6377), [\#6522](https://github.com/matrix-org/synapse/issues/6522))
- Prevent error on trying to search a upgraded room when the server is not in the predecessor room. ([\#6385](https://github.com/matrix-org/synapse/issues/6385))
- Improve performance of looking up cross-signing keys. ([\#6486](https://github.com/matrix-org/synapse/issues/6486))
- Fix race which occasionally caused deleted devices to reappear. ([\#6514](https://github.com/matrix-org/synapse/issues/6514))
- Fix missing row in `device_max_stream_id` that could cause unable to decrypt errors after server restart. ([\#6555](https://github.com/matrix-org/synapse/issues/6555))
- Fix a bug which meant that we did not send systemd notifications on startup if acme was enabled. ([\#6571](https://github.com/matrix-org/synapse/issues/6571))
- Fix exception when fetching the `matrix.org:ed25519:auto` key. ([\#6625](https://github.com/matrix-org/synapse/issues/6625))
- Fix bug where a moderator upgraded a room and became an admin in the new room. ([\#6633](https://github.com/matrix-org/synapse/issues/6633))
- Fix an error which was thrown by the `PresenceHandler` `_on_shutdown` handler. ([\#6640](https://github.com/matrix-org/synapse/issues/6640))
- Fix exceptions in the synchrotron worker log when events are rejected. ([\#6645](https://github.com/matrix-org/synapse/issues/6645))
- Ensure that upgraded rooms are removed from the directory. ([\#6648](https://github.com/matrix-org/synapse/issues/6648))
- Fix a bug causing Synapse not to fetch missing events when it believes it has every event in the room. ([\#6652](https://github.com/matrix-org/synapse/issues/6652))


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

- Document the Room Shutdown Admin API. ([\#6541](https://github.com/matrix-org/synapse/issues/6541))
- Reword sections of [docs/federate.md](docs/federate.md) that explained delegation at time of Synapse 1.0 transition. ([\#6601](https://github.com/matrix-org/synapse/issues/6601))
- Added the section 'Configuration' in [docs/turn-howto.md](docs/turn-howto.md). ([\#6614](https://github.com/matrix-org/synapse/issues/6614))


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

- Remove redundant code from event authorisation implementation. ([\#6502](https://github.com/matrix-org/synapse/issues/6502))
- Remove unused, undocumented `/_matrix/content` API. ([\#6628](https://github.com/matrix-org/synapse/issues/6628))


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

- Add *experimental* support for multiple physical databases and split out state storage to separate data store. ([\#6245](https://github.com/matrix-org/synapse/issues/6245), [\#6510](https://github.com/matrix-org/synapse/issues/6510), [\#6511](https://github.com/matrix-org/synapse/issues/6511), [\#6513](https://github.com/matrix-org/synapse/issues/6513), [\#6564](https://github.com/matrix-org/synapse/issues/6564), [\#6565](https://github.com/matrix-org/synapse/issues/6565))
- Port sections of code base to async/await. ([\#6496](https://github.com/matrix-org/synapse/issues/6496), [\#6504](https://github.com/matrix-org/synapse/issues/6504), [\#6505](https://github.com/matrix-org/synapse/issues/6505), [\#6517](https://github.com/matrix-org/synapse/issues/6517), [\#6559](https://github.com/matrix-org/synapse/issues/6559), [\#6647](https://github.com/matrix-org/synapse/issues/6647), [\#6653](https://github.com/matrix-org/synapse/issues/6653))
- Remove `SnapshotCache` in favour of `ResponseCache`. ([\#6506](https://github.com/matrix-org/synapse/issues/6506))
- Silence mypy errors for files outside those specified. ([\#6512](https://github.com/matrix-org/synapse/issues/6512))
- Clean up some logging when handling incoming events over federation. ([\#6515](https://github.com/matrix-org/synapse/issues/6515))
- Test more folders against mypy. ([\#6534](https://github.com/matrix-org/synapse/issues/6534))
- Update `mypy` to new version. ([\#6537](https://github.com/matrix-org/synapse/issues/6537))
- Adjust the sytest blacklist for worker mode. ([\#6538](https://github.com/matrix-org/synapse/issues/6538))
- Remove unused `get_pagination_rows` methods from `EventSource` classes. ([\#6557](https://github.com/matrix-org/synapse/issues/6557))
- Clean up logs from the push notifier at startup. ([\#6558](https://github.com/matrix-org/synapse/issues/6558))
- Improve diagnostics on database upgrade failure. ([\#6570](https://github.com/matrix-org/synapse/issues/6570))
- Reduce the reconnect time when worker replication fails, to make it easier to catch up. ([\#6617](https://github.com/matrix-org/synapse/issues/6617))
- Simplify http handling by removing redundant `SynapseRequestFactory`. ([\#6619](https://github.com/matrix-org/synapse/issues/6619))
- Add a workaround for synapse raising exceptions when fetching the notary's own key from the notary. ([\#6620](https://github.com/matrix-org/synapse/issues/6620))
- Automate generation of the sample log config. ([\#6627](https://github.com/matrix-org/synapse/issues/6627))
- Simplify event creation code by removing redundant queries on the `event_reference_hashes` table. ([\#6629](https://github.com/matrix-org/synapse/issues/6629))
- Fix errors when `frozen_dicts` are enabled. ([\#6642](https://github.com/matrix-org/synapse/issues/6642))


Synapse 1.7.3 (2019-12-31)
==========================

This release fixes a long-standing bug in the state resolution algorithm.

Bugfixes
--------

- Fix exceptions caused by state resolution choking on malformed events. ([\#6608](https://github.com/matrix-org/synapse/issues/6608))


Synapse 1.7.2 (2019-12-20)
==========================

This release fixes some regressions introduced in Synapse 1.7.0 and 1.7.1.

Bugfixes
--------

- Fix a regression introduced in Synapse 1.7.1 which caused errors when attempting to backfill rooms over federation. ([\#6576](https://github.com/matrix-org/synapse/issues/6576))
- Fix a bug introduced in Synapse 1.7.0 which caused an error on startup when upgrading from versions before 1.3.0. ([\#6578](https://github.com/matrix-org/synapse/issues/6578))


Synapse 1.7.1 (2019-12-18)
==========================

This release includes several security fixes as well as a fix to a bug exposed by the security fixes. Administrators are encouraged to upgrade as soon as possible.

Security updates
----------------

- Fix a bug which could cause room events to be incorrectly authorized using events from a different room. ([\#6501](https://github.com/matrix-org/synapse/issues/6501), [\#6503](https://github.com/matrix-org/synapse/issues/6503), [\#6521](https://github.com/matrix-org/synapse/issues/6521), [\#6524](https://github.com/matrix-org/synapse/issues/6524), [\#6530](https://github.com/matrix-org/synapse/issues/6530), [\#6531](https://github.com/matrix-org/synapse/issues/6531))
- Fix a bug causing responses to the `/context` client endpoint to not use the pruned version of the event. ([\#6553](https://github.com/matrix-org/synapse/issues/6553))
- Fix a cause of state resets in room versions 2 onwards. ([\#6556](https://github.com/matrix-org/synapse/issues/6556), [\#6560](https://github.com/matrix-org/synapse/issues/6560))

Bugfixes
--------

- Fix a bug which could cause the federation server to incorrectly return errors when handling certain obscure event graphs. ([\#6526](https://github.com/matrix-org/synapse/issues/6526), [\#6527](https://github.com/matrix-org/synapse/issues/6527))

Synapse 1.7.0 (2019-12-13)
==========================

This release changes the default settings so that only local authenticated users can query the server's room directory. See the [upgrade notes](docs/upgrade.md#upgrading-to-v170) for details.

Support for SQLite versions before 3.11 is now deprecated. A future release will refuse to start if used with an SQLite version before 3.11.

Administrators are reminded that SQLite should not be used for production instances. Instructions for migrating to Postgres are available [here](docs/postgres.md). A future release of synapse will, by default, disable federation for servers using SQLite.

No significant changes since 1.7.0rc2.


Synapse 1.7.0rc2 (2019-12-11)
=============================

Bugfixes
--------

- Fix incorrect error message for invalid requests when setting user's avatar URL. ([\#6497](https://github.com/matrix-org/synapse/issues/6497))
- Fix support for SQLite 3.7. ([\#6499](https://github.com/matrix-org/synapse/issues/6499))
- Fix regression where sending email push would not work when using a pusher worker. ([\#6507](https://github.com/matrix-org/synapse/issues/6507), [\#6509](https://github.com/matrix-org/synapse/issues/6509))


Synapse 1.7.0rc1 (2019-12-09)
=============================

Features
--------

- Implement per-room message retention policies. ([\#5815](https://github.com/matrix-org/synapse/issues/5815), [\#6436](https://github.com/matrix-org/synapse/issues/6436))
- Add etag and count fields to key backup endpoints to help clients guess if there are new keys. ([\#5858](https://github.com/matrix-org/synapse/issues/5858))
- Add `/admin/v2/users` endpoint with pagination. Contributed by Awesome Technologies Innovationslabor GmbH. ([\#5925](https://github.com/matrix-org/synapse/issues/5925))
- Require User-Interactive Authentication for `/account/3pid/add`, meaning the user's password will be required to add a third-party ID to their account. ([\#6119](https://github.com/matrix-org/synapse/issues/6119))
- Implement the `/_matrix/federation/unstable/net.atleastfornow/state/<context>` API as drafted in MSC2314. ([\#6176](https://github.com/matrix-org/synapse/issues/6176))
- Configure privacy-preserving settings by default for the room directory. ([\#6355](https://github.com/matrix-org/synapse/issues/6355))
- Add ephemeral messages support by partially implementing [MSC2228](https://github.com/matrix-org/matrix-doc/pull/2228). ([\#6409](https://github.com/matrix-org/synapse/issues/6409))
- Add support for [MSC 2367](https://github.com/matrix-org/matrix-doc/pull/2367), which allows specifying a reason on all membership events. ([\#6434](https://github.com/matrix-org/synapse/issues/6434))


Bugfixes
--------

- Transfer non-standard power levels on room upgrade. ([\#6237](https://github.com/matrix-org/synapse/issues/6237))
- Fix error from the Pillow library when uploading RGBA images. ([\#6241](https://github.com/matrix-org/synapse/issues/6241))
- Correctly apply the event filter to the `state`, `events_before` and `events_after` fields in the response to `/context` requests. ([\#6329](https://github.com/matrix-org/synapse/issues/6329))
- Fix caching devices for remote users when using workers, so that we don't attempt to refetch (and potentially fail) each time a user requests devices. ([\#6332](https://github.com/matrix-org/synapse/issues/6332))
- Prevent account data syncs getting lost across TCP replication. ([\#6333](https://github.com/matrix-org/synapse/issues/6333))
- Fix bug: TypeError in `register_user()` while using LDAP auth module. ([\#6406](https://github.com/matrix-org/synapse/issues/6406))
- Fix an intermittent exception when handling read-receipts. ([\#6408](https://github.com/matrix-org/synapse/issues/6408))
- Fix broken guest registration when there are existing blocks of numeric user IDs. ([\#6420](https://github.com/matrix-org/synapse/issues/6420))
- Fix startup error when http proxy is defined. ([\#6421](https://github.com/matrix-org/synapse/issues/6421))
- Fix error when using synapse_port_db on a vanilla synapse db. ([\#6449](https://github.com/matrix-org/synapse/issues/6449))
- Fix uploading multiple cross signing signatures for the same user. ([\#6451](https://github.com/matrix-org/synapse/issues/6451))
- Fix bug which lead to exceptions being thrown in a loop when a cross-signed device is deleted. ([\#6462](https://github.com/matrix-org/synapse/issues/6462))
- Fix `synapse_port_db` not exiting with a 0 code if something went wrong during the port process. ([\#6470](https://github.com/matrix-org/synapse/issues/6470))
- Improve sanity-checking when receiving events over federation. ([\#6472](https://github.com/matrix-org/synapse/issues/6472))
- Fix inaccurate per-block Prometheus metrics. ([\#6491](https://github.com/matrix-org/synapse/issues/6491))
- Fix small performance regression for sending invites. ([\#6493](https://github.com/matrix-org/synapse/issues/6493))
- Back out cross-signing code added in Synapse 1.5.0, which caused a performance regression. ([\#6494](https://github.com/matrix-org/synapse/issues/6494))


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

- Update documentation and variables in user contributed systemd reference file. ([\#6369](https://github.com/matrix-org/synapse/issues/6369), [\#6490](https://github.com/matrix-org/synapse/issues/6490))
- Fix link in the user directory documentation. ([\#6388](https://github.com/matrix-org/synapse/issues/6388))
- Add build instructions to the docker readme. ([\#6390](https://github.com/matrix-org/synapse/issues/6390))
- Switch Ubuntu package install recommendation to use python3 packages in INSTALL.md. ([\#6443](https://github.com/matrix-org/synapse/issues/6443))
- Write some docs for the quarantine_media api. ([\#6458](https://github.com/matrix-org/synapse/issues/6458))
- Convert CONTRIBUTING.rst to markdown (among other small fixes). ([\#6461](https://github.com/matrix-org/synapse/issues/6461))


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

- Remove admin/v1/users_paginate endpoint. Contributed by Awesome Technologies Innovationslabor GmbH. ([\#5925](https://github.com/matrix-org/synapse/issues/5925))
- Remove fallback for federation with old servers which lack the /federation/v1/state_ids API. ([\#6488](https://github.com/matrix-org/synapse/issues/6488))


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

- Add benchmarks for structured logging and improve output performance. ([\#6266](https://github.com/matrix-org/synapse/issues/6266))
- Improve the performance of outputting structured logging. ([\#6322](https://github.com/matrix-org/synapse/issues/6322))
- Refactor some code in the event authentication path for clarity. ([\#6343](https://github.com/matrix-org/synapse/issues/6343), [\#6468](https://github.com/matrix-org/synapse/issues/6468), [\#6480](https://github.com/matrix-org/synapse/issues/6480))
- Clean up some unnecessary quotation marks around the codebase. ([\#6362](https://github.com/matrix-org/synapse/issues/6362))
- Complain on startup instead of 500'ing during runtime when `public_baseurl` isn't set when necessary. ([\#6379](https://github.com/matrix-org/synapse/issues/6379))
- Add a test scenario to make sure room history purges don't break `/messages` in the future. ([\#6392](https://github.com/matrix-org/synapse/issues/6392))
- Clarifications for the email configuration settings. ([\#6423](https://github.com/matrix-org/synapse/issues/6423))
- Add more tests to the blacklist when running in worker mode. ([\#6429](https://github.com/matrix-org/synapse/issues/6429))
- Refactor data store layer to support multiple databases in the future. ([\#6454](https://github.com/matrix-org/synapse/issues/6454), [\#6464](https://github.com/matrix-org/synapse/issues/6464), [\#6469](https://github.com/matrix-org/synapse/issues/6469), [\#6487](https://github.com/matrix-org/synapse/issues/6487))
- Port synapse.rest.client.v1 to async/await. ([\#6482](https://github.com/matrix-org/synapse/issues/6482))
- Port synapse.rest.client.v2_alpha to async/await. ([\#6483](https://github.com/matrix-org/synapse/issues/6483))
- Port SyncHandler to async/await. ([\#6484](https://github.com/matrix-org/synapse/issues/6484))

Synapse 1.6.1 (2019-11-28)
==========================

Security updates
----------------

This release includes a security fix ([\#6426](https://github.com/matrix-org/synapse/issues/6426), below). Administrators are encouraged to upgrade as soon as possible.

Bugfixes
--------

- Clean up local threepids from user on account deactivation. ([\#6426](https://github.com/matrix-org/synapse/issues/6426))
- Fix startup error when http proxy is defined. ([\#6421](https://github.com/matrix-org/synapse/issues/6421))


Synapse 1.6.0 (2019-11-26)
==========================

Bugfixes
--------

- Fix phone home stats reporting. ([\#6418](https://github.com/matrix-org/synapse/issues/6418))


Synapse 1.6.0rc2 (2019-11-25)
=============================

Bugfixes
--------

- Fix a bug which could cause the background database update hander for event labels to get stuck in a loop raising exceptions. ([\#6407](https://github.com/matrix-org/synapse/issues/6407))


Synapse 1.6.0rc1 (2019-11-20)
=============================

Features
--------

- Add federation support for cross-signing. ([\#5727](https://github.com/matrix-org/synapse/issues/5727))
- Increase default room version from 4 to 5, thereby enforcing server key validity period checks. ([\#6220](https://github.com/matrix-org/synapse/issues/6220))
- Add support for outbound http proxying via http_proxy/HTTPS_PROXY env vars. ([\#6238](https://github.com/matrix-org/synapse/issues/6238))
- Implement label-based filtering on `/sync` and `/messages` ([MSC2326](https://github.com/matrix-org/matrix-doc/pull/2326)). ([\#6301](https://github.com/matrix-org/synapse/issues/6301), [\#6310](https://github.com/matrix-org/synapse/issues/6310), [\#6340](https://github.com/matrix-org/synapse/issues/6340))


Bugfixes
--------

- Fix LruCache callback deduplication for Python 3.8. Contributed by @V02460. ([\#6213](https://github.com/matrix-org/synapse/issues/6213))
- Remove a room from a server's public rooms list on room upgrade. ([\#6232](https://github.com/matrix-org/synapse/issues/6232), [\#6235](https://github.com/matrix-org/synapse/issues/6235))
- Delete keys from key backup when deleting backup versions. ([\#6253](https://github.com/matrix-org/synapse/issues/6253))
- Make notification of cross-signing signatures work with workers. ([\#6254](https://github.com/matrix-org/synapse/issues/6254))
- Fix exception when remote servers attempt to join a room that they're not allowed to join. ([\#6278](https://github.com/matrix-org/synapse/issues/6278))
- Prevent errors from appearing on Synapse startup if `git` is not installed. ([\#6284](https://github.com/matrix-org/synapse/issues/6284))
- Appservice requests will no longer contain a double slash prefix when the appservice url provided ends in a slash. ([\#6306](https://github.com/matrix-org/synapse/issues/6306))
- Fix `/purge_room` admin API. ([\#6307](https://github.com/matrix-org/synapse/issues/6307))
- Fix the `hidden` field in the `devices` table for SQLite versions prior to 3.23.0. ([\#6313](https://github.com/matrix-org/synapse/issues/6313))
- Fix bug which casued rejected events to be persisted with the wrong room state. ([\#6320](https://github.com/matrix-org/synapse/issues/6320))
- Fix bug where `rc_login` ratelimiting would prematurely kick in. ([\#6335](https://github.com/matrix-org/synapse/issues/6335))
- Prevent the server taking a long time to start up when guest registration is enabled. ([\#6338](https://github.com/matrix-org/synapse/issues/6338))
- Fix bug where upgrading a guest account to a full user would fail when account validity is enabled. ([\#6359](https://github.com/matrix-org/synapse/issues/6359))
- Fix `to_device` stream ID getting reset every time Synapse restarts, which had the potential to cause unable to decrypt errors. ([\#6363](https://github.com/matrix-org/synapse/issues/6363))
- Fix permission denied error when trying to generate a config file with the docker image. ([\#6389](https://github.com/matrix-org/synapse/issues/6389))


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

- Contributor documentation now mentions script to run linters. ([\#6164](https://github.com/matrix-org/synapse/issues/6164))
- Modify CAPTCHA_SETUP.md to update the terms `private key` and `public key` to `secret key` and `site key` respectively. Contributed by Yash Jipkate. ([\#6257](https://github.com/matrix-org/synapse/issues/6257))
- Update `INSTALL.md` Email section to talk about `account_threepid_delegates`. ([\#6272](https://github.com/matrix-org/synapse/issues/6272))
- Fix a small typo in `account_threepid_delegates` configuration option. ([\#6273](https://github.com/matrix-org/synapse/issues/6273))


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

- Add a CI job to test the `synapse_port_db` script. ([\#6140](https://github.com/matrix-org/synapse/issues/6140), [\#6276](https://github.com/matrix-org/synapse/issues/6276))
- Convert EventContext to an attrs. ([\#6218](https://github.com/matrix-org/synapse/issues/6218))
- Move `persist_events` out from main data store. ([\#6240](https://github.com/matrix-org/synapse/issues/6240), [\#6300](https://github.com/matrix-org/synapse/issues/6300))
- Reduce verbosity of user/room stats. ([\#6250](https://github.com/matrix-org/synapse/issues/6250))
- Reduce impact of debug logging. ([\#6251](https://github.com/matrix-org/synapse/issues/6251))
- Expose some homeserver functionality to spam checkers. ([\#6259](https://github.com/matrix-org/synapse/issues/6259))
- Change cache descriptors to always return deferreds. ([\#6263](https://github.com/matrix-org/synapse/issues/6263), [\#6291](https://github.com/matrix-org/synapse/issues/6291))
- Fix incorrect comment regarding the functionality of an `if` statement. ([\#6269](https://github.com/matrix-org/synapse/issues/6269))
- Update CI to run `isort` over the `scripts` and `scripts-dev` directories. ([\#6270](https://github.com/matrix-org/synapse/issues/6270))
- Replace every instance of `logger.warn` method with `logger.warning` as the former is deprecated. ([\#6271](https://github.com/matrix-org/synapse/issues/6271), [\#6314](https://github.com/matrix-org/synapse/issues/6314))
- Port replication http server endpoints to async/await. ([\#6274](https://github.com/matrix-org/synapse/issues/6274))
- Port room rest handlers to async/await. ([\#6275](https://github.com/matrix-org/synapse/issues/6275))
- Remove redundant CLI parameters on CI's `flake8` step. ([\#6277](https://github.com/matrix-org/synapse/issues/6277))
- Port `federation_server.py` to async/await. ([\#6279](https://github.com/matrix-org/synapse/issues/6279))
- Port receipt and read markers to async/wait. ([\#6280](https://github.com/matrix-org/synapse/issues/6280))
- Split out state storage into separate data store. ([\#6294](https://github.com/matrix-org/synapse/issues/6294), [\#6295](https://github.com/matrix-org/synapse/issues/6295))
- Refactor EventContext for clarity. ([\#6298](https://github.com/matrix-org/synapse/issues/6298))
- Update the version of black used to 19.10b0. ([\#6304](https://github.com/matrix-org/synapse/issues/6304))
- Add some documentation about worker replication. ([\#6305](https://github.com/matrix-org/synapse/issues/6305))
- Move admin endpoints into separate files. Contributed by Awesome Technologies Innovationslabor GmbH. ([\#6308](https://github.com/matrix-org/synapse/issues/6308))
- Document the use of `lint.sh` for code style enforcement & extend it to run on specified paths only. ([\#6312](https://github.com/matrix-org/synapse/issues/6312))
- Add optional python dependencies and dependant binary libraries to snapcraft packaging. ([\#6317](https://github.com/matrix-org/synapse/issues/6317))
- Remove the dependency on psutil and replace functionality with the stdlib `resource` module. ([\#6318](https://github.com/matrix-org/synapse/issues/6318), [\#6336](https://github.com/matrix-org/synapse/issues/6336))
- Improve documentation for EventContext fields. ([\#6319](https://github.com/matrix-org/synapse/issues/6319))
- Add some checks that we aren't using state from rejected events. ([\#6330](https://github.com/matrix-org/synapse/issues/6330))
- Add continuous integration for python 3.8. ([\#6341](https://github.com/matrix-org/synapse/issues/6341))
- Correct spacing/case of various instances of the word "homeserver". ([\#6357](https://github.com/matrix-org/synapse/issues/6357))
- Temporarily blacklist the failing unit test PurgeRoomTestCase.test_purge_room. ([\#6361](https://github.com/matrix-org/synapse/issues/6361))


Synapse 1.5.1 (2019-11-06)
==========================

Features
--------

- Limit the length of data returned by url previews, to prevent DoS attacks. ([\#6331](https://github.com/matrix-org/synapse/issues/6331), [\#6334](https://github.com/matrix-org/synapse/issues/6334))


Synapse 1.5.0 (2019-10-29)
==========================

Security updates
----------------

This release includes a security fix ([\#6262](https://github.com/matrix-org/synapse/issues/6262), below). Administrators are encouraged to upgrade as soon as possible.

Bugfixes
--------

- Fix bug where room directory search was case sensitive. ([\#6268](https://github.com/matrix-org/synapse/issues/6268))


Synapse 1.5.0rc2 (2019-10-28)
=============================

Bugfixes
--------

- Update list of boolean columns in `synapse_port_db`. ([\#6247](https://github.com/matrix-org/synapse/issues/6247))
- Fix /keys/query API on workers. ([\#6256](https://github.com/matrix-org/synapse/issues/6256))
- Improve signature checking on some federation APIs. ([\#6262](https://github.com/matrix-org/synapse/issues/6262))


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

- Move schema delta files to the correct data store. ([\#6248](https://github.com/matrix-org/synapse/issues/6248))
- Small performance improvement by removing repeated config lookups in room stats calculation. ([\#6255](https://github.com/matrix-org/synapse/issues/6255))


Synapse 1.5.0rc1 (2019-10-24)
==========================

Features
--------

- Improve quality of thumbnails for 1-bit/8-bit color palette images. ([\#2142](https://github.com/matrix-org/synapse/issues/2142))
- Add ability to upload cross-signing signatures. ([\#5726](https://github.com/matrix-org/synapse/issues/5726))
- Allow uploading of cross-signing keys. ([\#5769](https://github.com/matrix-org/synapse/issues/5769))
- CAS login now provides a default display name for users if a `displayname_attribute` is set in the configuration file. ([\#6114](https://github.com/matrix-org/synapse/issues/6114))
- Reject all pending invites for a user during deactivation. ([\#6125](https://github.com/matrix-org/synapse/issues/6125))
- Add config option to suppress client side resource limit alerting. ([\#6173](https://github.com/matrix-org/synapse/issues/6173))


Bugfixes
--------

- Return an HTTP 404 instead of 400 when requesting a filter by ID that is unknown to the server. Thanks to @krombel for contributing this! ([\#2380](https://github.com/matrix-org/synapse/issues/2380))
- Fix a bug where users could be invited twice to the same group. ([\#3436](https://github.com/matrix-org/synapse/issues/3436))
- Fix `/createRoom` failing with badly-formatted MXIDs in the invitee list. Thanks to @wener291! ([\#4088](https://github.com/matrix-org/synapse/issues/4088))
- Make the `synapse_port_db` script create the right indexes on a new PostgreSQL database. ([\#6102](https://github.com/matrix-org/synapse/issues/6102), [\#6178](https://github.com/matrix-org/synapse/issues/6178), [\#6243](https://github.com/matrix-org/synapse/issues/6243))
- Fix bug when uploading a large file: Synapse responds with `M_UNKNOWN` while it should be `M_TOO_LARGE` according to spec. Contributed by Anshul Angaria. ([\#6109](https://github.com/matrix-org/synapse/issues/6109))
- Fix user push rules being deleted from a room when it is upgraded. ([\#6144](https://github.com/matrix-org/synapse/issues/6144))
- Don't 500 when trying to exchange a revoked 3PID invite. ([\#6147](https://github.com/matrix-org/synapse/issues/6147))
- Fix transferring notifications and tags when joining an upgraded room that is new to your server. ([\#6155](https://github.com/matrix-org/synapse/issues/6155))
- Fix bug where guest account registration can wedge after restart. ([\#6161](https://github.com/matrix-org/synapse/issues/6161))
- Fix monthly active user reaping when reserved users are specified. ([\#6168](https://github.com/matrix-org/synapse/issues/6168))
- Fix `/federation/v1/state` endpoint not supporting newer room versions. ([\#6170](https://github.com/matrix-org/synapse/issues/6170))
- Fix bug where we were updating censored events as bytes rather than text, occaisonally causing invalid JSON being inserted breaking APIs that attempted to fetch such events. ([\#6186](https://github.com/matrix-org/synapse/issues/6186))
- Fix occasional missed updates in the room and user directories. ([\#6187](https://github.com/matrix-org/synapse/issues/6187))
- Fix tracing of non-JSON APIs, `/media`, `/key` etc. ([\#6195](https://github.com/matrix-org/synapse/issues/6195))
- Fix bug where presence would not get timed out correctly if a synchrotron worker is used and restarted. ([\#6212](https://github.com/matrix-org/synapse/issues/6212))
- synapse_port_db: Add 2 additional BOOLEAN_COLUMNS to be able to convert from database schema v56. ([\#6216](https://github.com/matrix-org/synapse/issues/6216))
- Fix a bug where the Synapse demo script blacklisted `::1` (ipv6 localhost) from receiving federation traffic. ([\#6229](https://github.com/matrix-org/synapse/issues/6229))


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

- Fix logging getting lost for the docker image. ([\#6197](https://github.com/matrix-org/synapse/issues/6197))


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

- Update `user_filters` table to have a unique index, and non-null columns. Thanks to @pik for contributing this. ([\#1172](https://github.com/matrix-org/synapse/issues/1172), [\#6175](https://github.com/matrix-org/synapse/issues/6175), [\#6184](https://github.com/matrix-org/synapse/issues/6184))
- Allow devices to be marked as hidden, for use by features such as cross-signing.
  This adds a new field with a default value to the devices field in the database,
  and so the database upgrade may take a long time depending on how many devices
  are in the database. ([\#5759](https://github.com/matrix-org/synapse/issues/5759))
- Move lookup-related functions from RoomMemberHandler to IdentityHandler. ([\#5978](https://github.com/matrix-org/synapse/issues/5978))
- Improve performance of the public room list directory. ([\#6019](https://github.com/matrix-org/synapse/issues/6019), [\#6152](https://github.com/matrix-org/synapse/issues/6152), [\#6153](https://github.com/matrix-org/synapse/issues/6153), [\#6154](https://github.com/matrix-org/synapse/issues/6154))
- Edit header dicts docstrings in `SimpleHttpClient` to note that `str` or `bytes` can be passed as header keys. ([\#6077](https://github.com/matrix-org/synapse/issues/6077))
- Add snapcraft packaging information. Contributed by @devec0. ([\#6084](https://github.com/matrix-org/synapse/issues/6084), [\#6191](https://github.com/matrix-org/synapse/issues/6191))
- Kill off half-implemented password-reset via sms. ([\#6101](https://github.com/matrix-org/synapse/issues/6101))
- Remove `get_user_by_req` opentracing span and add some tags. ([\#6108](https://github.com/matrix-org/synapse/issues/6108))
- Drop some unused database tables. ([\#6115](https://github.com/matrix-org/synapse/issues/6115))
- Add env var to turn on tracking of log context changes. ([\#6127](https://github.com/matrix-org/synapse/issues/6127))
- Refactor configuration loading to allow better typechecking. ([\#6137](https://github.com/matrix-org/synapse/issues/6137))
- Log responder when responding to media request. ([\#6139](https://github.com/matrix-org/synapse/issues/6139))
- Improve performance of `find_next_generated_user_id` DB query. ([\#6148](https://github.com/matrix-org/synapse/issues/6148))
- Expand type-checking on modules imported by `synapse.config`. ([\#6150](https://github.com/matrix-org/synapse/issues/6150))
- Use Postgres ANY for selecting many values. ([\#6156](https://github.com/matrix-org/synapse/issues/6156))
- Add more caching to `_get_joined_users_from_context` DB query. ([\#6159](https://github.com/matrix-org/synapse/issues/6159))
- Add some metrics on the federation sender. ([\#6160](https://github.com/matrix-org/synapse/issues/6160))
- Add some logging to the rooms stats updates, to try to track down a flaky test. ([\#6167](https://github.com/matrix-org/synapse/issues/6167))
- Remove unused `timeout` parameter from `_get_public_room_list`. ([\#6179](https://github.com/matrix-org/synapse/issues/6179))
- Reject (accidental) attempts to insert bytes into postgres tables. ([\#6186](https://github.com/matrix-org/synapse/issues/6186))
- Make `version` optional in body of `PUT /room_keys/version/{version}`, since it's redundant. ([\#6189](https://github.com/matrix-org/synapse/issues/6189))
- Make storage layer responsible for adding device names to key, rather than the handler. ([\#6193](https://github.com/matrix-org/synapse/issues/6193))
- Port `synapse.rest.admin` module to use async/await. ([\#6196](https://github.com/matrix-org/synapse/issues/6196))
- Enforce that all boolean configuration values are lowercase in CI. ([\#6203](https://github.com/matrix-org/synapse/issues/6203))
- Remove some unused event-auth code. ([\#6214](https://github.com/matrix-org/synapse/issues/6214))
- Remove `Auth.check` method. ([\#6217](https://github.com/matrix-org/synapse/issues/6217))
- Remove `format_tap.py` script in favour of a perl reimplementation in Sytest's repo. ([\#6219](https://github.com/matrix-org/synapse/issues/6219))
- Refactor storage layer in preparation to support having multiple databases. ([\#6231](https://github.com/matrix-org/synapse/issues/6231))
- Remove some extra quotation marks across the codebase. ([\#6236](https://github.com/matrix-org/synapse/issues/6236))


Synapse 1.4.1 (2019-10-18)
==========================

No changes since 1.4.1rc1.


Synapse 1.4.1rc1 (2019-10-17)
=============================

Bugfixes
--------

- Fix bug where redacted events were sometimes incorrectly censored in the database, breaking APIs that attempted to fetch such events. ([\#6185](https://github.com/matrix-org/synapse/issues/6185), [5b0e9948](https://github.com/matrix-org/synapse/commit/5b0e9948eaae801643e594b5abc8ee4b10bd194e))

Synapse 1.4.0 (2019-10-03)
==========================

Bugfixes
--------

- Redact `client_secret` in server logs. ([\#6158](https://github.com/matrix-org/synapse/issues/6158))


Synapse 1.4.0rc2 (2019-10-02)
=============================

Bugfixes
--------

- Fix bug in background update that adds last seen information to the `devices` table, and improve its performance on Postgres. ([\#6135](https://github.com/matrix-org/synapse/issues/6135))
- Fix bad performance of censoring redactions background task. ([\#6141](https://github.com/matrix-org/synapse/issues/6141))
- Fix fetching censored redactions from DB, which caused APIs like initial sync to fail if it tried to include the censored redaction. ([\#6145](https://github.com/matrix-org/synapse/issues/6145))
- Fix exceptions when storing large retry intervals for down remote servers. ([\#6146](https://github.com/matrix-org/synapse/issues/6146))


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

- Fix up sample config entry for `redaction_retention_period` option. ([\#6117](https://github.com/matrix-org/synapse/issues/6117))


Synapse 1.4.0rc1 (2019-09-26)
=============================

Note that this release includes significant changes around 3pid
verification. Administrators are reminded to review the [upgrade notes](docs/upgrade.md#upgrading-to-v140).

Features
--------

- Changes to 3pid verification:
  - Add the ability to send registration emails from the homeserver rather than delegating to an identity server. ([\#5835](https://github.com/matrix-org/synapse/issues/5835), [\#5940](https://github.com/matrix-org/synapse/issues/5940), [\#5993](https://github.com/matrix-org/synapse/issues/5993), [\#5994](https://github.com/matrix-org/synapse/issues/5994), [\#5868](https://github.com/matrix-org/synapse/issues/5868))
  - Replace `trust_identity_server_for_password_resets` config option with `account_threepid_delegates`, and make the `id_server` parameteter optional on `*/requestToken` endpoints, as per [MSC2263](https://github.com/matrix-org/matrix-doc/pull/2263). ([\#5876](https://github.com/matrix-org/synapse/issues/5876), [\#5969](https://github.com/matrix-org/synapse/issues/5969), [\#6028](https://github.com/matrix-org/synapse/issues/6028))
  - Switch to using the v2 Identity Service `/lookup` API where available, with fallback to v1. (Implements [MSC2134](https://github.com/matrix-org/matrix-doc/pull/2134) plus `id_access_token authentication` for v2 Identity Service APIs from [MSC2140](https://github.com/matrix-org/matrix-doc/pull/2140)). ([\#5897](https://github.com/matrix-org/synapse/issues/5897))
  - Remove `bind_email` and `bind_msisdn` parameters from `/register` ala [MSC2140](https://github.com/matrix-org/matrix-doc/pull/2140). ([\#5964](https://github.com/matrix-org/synapse/issues/5964))
  - Add `m.id_access_token` to `unstable_features` in `/versions` as per [MSC2264](https://github.com/matrix-org/matrix-doc/pull/2264). ([\#5974](https://github.com/matrix-org/synapse/issues/5974))
  - Use the v2 Identity Service API for 3PID invites. ([\#5979](https://github.com/matrix-org/synapse/issues/5979))
  - Add `POST /_matrix/client/unstable/account/3pid/unbind` endpoint from [MSC2140](https://github.com/matrix-org/matrix-doc/pull/2140) for unbinding a 3PID from an identity server without removing it from the homeserver user account. ([\#5980](https://github.com/matrix-org/synapse/issues/5980), [\#6062](https://github.com/matrix-org/synapse/issues/6062))
  - Use `account_threepid_delegate.email` and `account_threepid_delegate.msisdn` for validating threepid sessions. ([\#6011](https://github.com/matrix-org/synapse/issues/6011))
  - Allow homeserver to handle or delegate email validation when adding an email to a user's account. ([\#6042](https://github.com/matrix-org/synapse/issues/6042))
  - Implement new Client Server API endpoints `/account/3pid/add` and `/account/3pid/bind` as per [MSC2290](https://github.com/matrix-org/matrix-doc/pull/2290). ([\#6043](https://github.com/matrix-org/synapse/issues/6043))
  - Add an unstable feature flag for separate add/bind 3pid APIs. ([\#6044](https://github.com/matrix-org/synapse/issues/6044))
  - Remove `bind` parameter from Client Server POST `/account` endpoint as per [MSC2290](https://github.com/matrix-org/matrix-doc/pull/2290/). ([\#6067](https://github.com/matrix-org/synapse/issues/6067))
  - Add `POST /add_threepid/msisdn/submit_token` endpoint for proxying submitToken on an `account_threepid_handler`. ([\#6078](https://github.com/matrix-org/synapse/issues/6078))
  - Add `submit_url` response parameter to `*/msisdn/requestToken` endpoints. ([\#6079](https://github.com/matrix-org/synapse/issues/6079))
  - Add `m.require_identity_server` flag to /version's unstable_features. ([\#5972](https://github.com/matrix-org/synapse/issues/5972))
- Enhancements to OpenTracing support:
  - Make OpenTracing work in worker mode. ([\#5771](https://github.com/matrix-org/synapse/issues/5771))
  - Pass OpenTracing contexts between servers when transmitting EDUs. ([\#5852](https://github.com/matrix-org/synapse/issues/5852))
  - OpenTracing for device list updates. ([\#5853](https://github.com/matrix-org/synapse/issues/5853))
  - Add a tag recording a request's authenticated entity and corresponding servlet in OpenTracing. ([\#5856](https://github.com/matrix-org/synapse/issues/5856))
  - Add minimum OpenTracing for client servlets. ([\#5983](https://github.com/matrix-org/synapse/issues/5983))
  - Check at setup that OpenTracing is installed if it's enabled in the config. ([\#5985](https://github.com/matrix-org/synapse/issues/5985))
  - Trace replication send times. ([\#5986](https://github.com/matrix-org/synapse/issues/5986))
  - Include missing OpenTracing contexts in outbout replication requests. ([\#5982](https://github.com/matrix-org/synapse/issues/5982))
  - Fix sending of EDUs when OpenTracing is enabled with an empty whitelist. ([\#5984](https://github.com/matrix-org/synapse/issues/5984))
  - Fix invalid references to None while OpenTracing if the log context slips. ([\#5988](https://github.com/matrix-org/synapse/issues/5988), [\#5991](https://github.com/matrix-org/synapse/issues/5991))
  - OpenTracing for room and e2e keys. ([\#5855](https://github.com/matrix-org/synapse/issues/5855))
  - Add OpenTracing span over HTTP push processing. ([\#6003](https://github.com/matrix-org/synapse/issues/6003))
- Add an admin API to purge old rooms from the database. ([\#5845](https://github.com/matrix-org/synapse/issues/5845))
- Retry well-known lookups if we have recently seen a valid well-known record for the server. ([\#5850](https://github.com/matrix-org/synapse/issues/5850))
- Add support for filtered room-directory search requests over federation ([MSC2197](https://github.com/matrix-org/matrix-doc/pull/2197), in order to allow upcoming room directory query performance improvements. ([\#5859](https://github.com/matrix-org/synapse/issues/5859))
- Correctly retry all hosts returned from SRV when we fail to connect. ([\#5864](https://github.com/matrix-org/synapse/issues/5864))
- Add admin API endpoint for setting whether or not a user is a server administrator. ([\#5878](https://github.com/matrix-org/synapse/issues/5878))
- Enable cleaning up extremities with dummy events by default to prevent undue build up of forward extremities. ([\#5884](https://github.com/matrix-org/synapse/issues/5884))
- Add config option to sign remote key query responses with a separate key. ([\#5895](https://github.com/matrix-org/synapse/issues/5895))
- Add support for config templating. ([\#5900](https://github.com/matrix-org/synapse/issues/5900))
- Users with the type of "support" or "bot" are no longer required to consent. ([\#5902](https://github.com/matrix-org/synapse/issues/5902))
- Let synctl accept a directory of config files. ([\#5904](https://github.com/matrix-org/synapse/issues/5904))
- Increase max display name size to 256. ([\#5906](https://github.com/matrix-org/synapse/issues/5906))
- Add admin API endpoint for getting whether or not a user is a server administrator. ([\#5914](https://github.com/matrix-org/synapse/issues/5914))
- Redact events in the database that have been redacted for a week. ([\#5934](https://github.com/matrix-org/synapse/issues/5934))
- New prometheus metrics:
  - `synapse_federation_known_servers`: represents the total number of servers your server knows about (i.e. is in rooms with), including itself. Enable by setting `metrics_flags.known_servers` to True in the configuration.([\#5981](https://github.com/matrix-org/synapse/issues/5981))
  - `synapse_build_info`: exposes the Python version, OS version, and Synapse version of the running server. ([\#6005](https://github.com/matrix-org/synapse/issues/6005))
- Give appropriate exit codes when synctl fails. ([\#5992](https://github.com/matrix-org/synapse/issues/5992))
- Apply the federation blacklist to requests to identity servers. ([\#6000](https://github.com/matrix-org/synapse/issues/6000))