continuwuity/changelog.d/stateless-sync.md

The roomsynctoken_shortstatehash table — responsible for 60% to 90% of database bloat — has been removed. Sync state is now computed statelessly from the timeline on each request, eliminating the per-room write on every sync response. Existing table data is orphaned on disk and can be reclaimed by a future database compaction. Ref: #917