hydrogen-web/doc/impl-thoughts/CATCHUP-BACKFILL.md

we should automatically fill gaps (capped at a certain (large) amount of events, 5000?) after a limited sync for a room

E2EE rooms

during these fills (once supported), we should calculate push actions and trigger notifications, as we would otherwise have received this through sync.

we could also trigger notifications when just backfilling on initial sync up to a certain amount of time in the past?