- Add support for Ubuntu 21.10 "Impish Indri". ([\#11024](https://github.com/matrix-org/synapse/issues/11024))
- Port the Password Auth Providers module interface to the new generic interface. ([\#10548](https://github.com/matrix-org/synapse/issues/10548), [\#11180](https://github.com/matrix-org/synapse/issues/11180))
- Experimental support for the thread relation defined in [MSC3440](https://github.com/matrix-org/matrix-doc/pull/3440). ([\#11088](https://github.com/matrix-org/synapse/issues/11088), [\#11181](https://github.com/matrix-org/synapse/issues/11181))
- Experimental support for the thread relation defined in [MSC3440](https://github.com/matrix-org/matrix-doc/pull/3440). ([\#11088](https://github.com/matrix-org/synapse/issues/11088), [\#11181](https://github.com/matrix-org/synapse/issues/11181), [\#11192](https://github.com/matrix-org/synapse/issues/11192))
- Users admin API can now also modify user type in addition to allowing it to be set on user creation. ([\#11174](https://github.com/matrix-org/synapse/issues/11174))
@ -27,7 +27,7 @@ Bugfixes
- Fix a bug which caused the module API's `get_user_ip_and_agents` function to always fail on workers. `get_user_ip_and_agents` was introduced in 1.44.0 and did not function correctly on worker processes at the time. ([\#11112](https://github.com/matrix-org/synapse/issues/11112))
- Identity server connection is no longer ignoring `ip_range_whitelist`. ([\#11120](https://github.com/matrix-org/synapse/issues/11120))
- Fix a bug introduced in Synapse 1.45.0 breaking the configuration file parsing script. ([\#11145](https://github.com/matrix-org/synapse/issues/11145))
- Fix a performance regression introduced in 1.44.0 which could cause client requests to time out when making large numbers of outbound requests. ([\#11177](https://github.com/matrix-org/synapse/issues/11177))
- Fix a performance regression introduced in 1.44.0 which could cause client requests to time out when making large numbers of outbound requests. ([\#11177](https://github.com/matrix-org/synapse/issues/11177), [\#11190](https://github.com/matrix-org/synapse/issues/11190))
- Resolve and share `state_groups` for all [MSC2716](https://github.com/matrix-org/matrix-doc/pull/2716) historical events in batch. ([\#10975](https://github.com/matrix-org/synapse/issues/10975))