- Improve cross-signing upload when using [MSC3861](https://github.com/matrix-org/matrix-spec-proposals/pull/3861) to use a custom UIA flow stage, with web fallback support. ([\#17509](https://github.com/element-hq/synapse/issues/17509)) - Return `400 M_BAD_JSON` upon attempting to complete various room actions with a non-local user ID and unknown room ID, rather than an internal server error. ([\#17607](https://github.com/element-hq/synapse/issues/17607)) - Fix authenticated media responses using a wrong limit when following redirects over federation. ([\#17626](https://github.com/element-hq/synapse/issues/17626)) - Fix bug where we returned the wrong `bump_stamp` for invites in sliding sync response, causing incorrect ordering of invites in the room list. ([\#17674](https://github.com/element-hq/synapse/issues/17674)) - Clarify that the admin api resource is only loaded on the main process and not workers. ([\#17590](https://github.com/element-hq/synapse/issues/17590)) - Fixed typo in `saml2_config` config [example](https://element-hq.github.io/synapse/latest/usage/configuration/config_documentation.html#saml2_config). ([\#17594](https://github.com/element-hq/synapse/issues/17594)) - Stabilise [MSC4156](https://github.com/matrix-org/matrix-spec-proposals/pull/4156) by removing the `msc4156_enabled` config setting and defaulting it to `true`. ([\#17650](https://github.com/element-hq/synapse/issues/17650)) - Update [MSC3861](https://github.com/matrix-org/matrix-spec-proposals/pull/3861) implementation: load the issuer and account management URLs from OIDC discovery. ([\#17407](https://github.com/element-hq/synapse/issues/17407)) - Pre-populate room data used in experimental [MSC3575](https://github.com/matrix-org/matrix-spec-proposals/pull/3575) Sliding Sync `/sync` endpoint for quick filtering/sorting. ([\#17512](https://github.com/element-hq/synapse/issues/17512), [\#17632](https://github.com/element-hq/synapse/issues/17632), [\#17633](https://github.com/element-hq/synapse/issues/17633), [\#17634](https://github.com/element-hq/synapse/issues/17634), [\#17635](https://github.com/element-hq/synapse/issues/17635), [\#17636](https://github.com/element-hq/synapse/issues/17636), [\#17641](https://github.com/element-hq/synapse/issues/17641), [\#17654](https://github.com/element-hq/synapse/issues/17654), [\#17673](https://github.com/element-hq/synapse/issues/17673)) - Store sliding sync per-connection state in the database. ([\#17599](https://github.com/element-hq/synapse/issues/17599), [\#17631](https://github.com/element-hq/synapse/issues/17631)) - Make the sliding sync `PerConnectionState` class immutable. ([\#17600](https://github.com/element-hq/synapse/issues/17600)) - Replace `isort` and `black` with `ruff`. ([\#17620](https://github.com/element-hq/synapse/issues/17620), [\#17643](https://github.com/element-hq/synapse/issues/17643)) - Sliding Sync: Split up `get_room_membership_for_user_at_to_token`. ([\#17629](https://github.com/element-hq/synapse/issues/17629)) - Use new database tables for sliding sync. ([\#17630](https://github.com/element-hq/synapse/issues/17630), [\#17649](https://github.com/element-hq/synapse/issues/17649)) - Prevent duplicate tags being added to Sliding Sync traces. ([\#17655](https://github.com/element-hq/synapse/issues/17655)) - Get `bump_stamp` from [new sliding sync tables](https://github.com/element-hq/synapse/pull/17512) which should be faster. ([\#17658](https://github.com/element-hq/synapse/issues/17658)) - Speed up incremental Sliding Sync requests by avoiding extra work. ([\#17665](https://github.com/element-hq/synapse/issues/17665)) - Small performance improvement in speeding up sliding sync. ([\#17666](https://github.com/element-hq/synapse/issues/17666), [\#17670](https://github.com/element-hq/synapse/issues/17670), [\#17672](https://github.com/element-hq/synapse/issues/17672)) - Speed up sliding sync by reducing number of database calls. ([\#17684](https://github.com/element-hq/synapse/issues/17684)) - Speed up sync by pulling out fewer events from the database. ([\#17688](https://github.com/element-hq/synapse/issues/17688)) * Bump authlib from 1.3.1 to 1.3.2. ([\#17679](https://github.com/element-hq/synapse/issues/17679)) * Bump idna from 3.7 to 3.8. ([\#17682](https://github.com/element-hq/synapse/issues/17682)) * Bump ruff from 0.6.2 to 0.6.4. ([\#17680](https://github.com/element-hq/synapse/issues/17680)) * Bump towncrier from 24.7.1 to 24.8.0. ([\#17645](https://github.com/element-hq/synapse/issues/17645)) * Bump twisted from 24.7.0rc1 to 24.7.0. ([\#17647](https://github.com/element-hq/synapse/issues/17647)) * Bump types-pillow from 10.2.0.20240520 to 10.2.0.20240822. ([\#17644](https://github.com/element-hq/synapse/issues/17644)) * Bump types-psycopg2 from 2.9.21.20240417 to 2.9.21.20240819. ([\#17646](https://github.com/element-hq/synapse/issues/17646)) * Bump types-setuptools from 71.1.0.20240818 to 74.1.0.20240907. ([\#17681](https://github.com/element-hq/synapse/issues/17681))