Element blocked on an infinite incremental sync

[BillCarsonFr]

My EA is locked trying to handle a sync that took forever to process, forcing the app to finaly go in background.

By switching the logs to verbose, I can see that that infinite time is taken by MatrixHQ, trying to process an insane amount of m.room.membership (54k+ in just one log file)

=> Some problem noticed

-> My app can't process the sync, and will then process until the app enters background. Then all is cancelled. When the app will foreground again it will restart to call synapse for the sync/ then start process and fail
=> Infinite loop consume data

Also there is an issue with to_device, they will get re process several times, causing BAD_MAC on EA (and An Olm message got replayed on Element R)

[BillCarsonFr]

https://github.com/matrix-org/element-android-rageshakes/issues/33756
https://github.com/matrix-org/element-android-rageshakes/issues/33755
https://github.com/matrix-org/element-android-rageshakes/issues/33753
https://github.com/matrix-org/element-android-rageshakes/issues/33751
https://github.com/matrix-org/element-android-rageshakes/issues/33747

[BillCarsonFr]

Maybe related to that #4669

[ouchadam]

could it also be related to the recent reports of high battery usage? (we haven't been able to confirm yet)

[sefidel]

Old issue, but I've been having this exact problem for a few months now.
Happens every single day while performing gappy sync (in the morning), and you have to either wait 1h+ for it to finally sync, or manually trigger initial sync via developer mode.

Is this going to be fixed, or is it abandoned in favour of sliding sync?