Synapse 1.150.0rc1 (2026-03-17)

Features

Add experimental support for the MSC4370 Federation API GET /extremities endpoint. (#19314)
MSC4140: Cancellable delayed events: When persisting a delayed event to the timeline, include its delay_id in the event's unsigned section in /sync responses to the event sender. (#19479)
Expose MSC4354 Sticky Events over the legacy (v3) /sync API. (#19487)
When Matrix Authentication Service (MAS) integration is enabled, allow MAS to set the user locked status in Synapse. (#19554)

Fix Build and push complement image CI job pointing to non-existent image. (#19523)
Fix a bug introduced in v1.26.0 that caused deactivated, erased users to not be removed from the user directory. (#19542)

In the Admin API documentation, always express path parameters as /<param> instead of as /$param. (#19307)
Update docs to clarify outbound_federation_restricted_to can also be used with the Secure Border Gateway (SBG). (#19517)
Unify Complement developer docs. (#19518)

Put membership updates in a background resumable task when changing the avatar or the display name. (#19311)
Add in-repo Complement test to sanity check Synapse version matches git checkout (testing what we think we are). (#19476)
Migrate dev dependencies to PEP 735 dependency groups. (#19490)
Remove the optional systemd-python dependency and the systemd extra on the synapse package. (#19491)
Avoid re-computing the event ID when cloning events. (#19527)
Allow caching of the /versions and /auth_metadata public endpoints. (#19530)
Add a few labels to the number groupings in the Processed request logs. (#19548)