I figured it out -- the problem is that you cannot change the encryption parameters for a room, as any new m.room.encryption events are explicitly ignored[1]. I

I figured it out -- the problem is that you cannot change the encryption parameters for a room, as any new m.room.encryption events are explicitly ignored[1]. I set up a new room and sent a custom state event and it worked. There is obviously a reason why you can't disable encryption once enabled, but it does suck that fields within m.room.encryption which are entirely advisory (since as far as I know the current implementation doesn't block messages that use old sessions) can't be changed. It's good to see that the session is being rolled somewhat frequently though. This does explain some of my questions about why the old-school key backups kept getting larger even though I haven't joined any new chats. [1]: https://github.com/matrix-org/matrix-js-sdk/blob/03a54353be98941c7e8c124393b386d0b6affc6f/src/crypto/index.js#L962-L968 https://github.com/matrix-org/matrix-js-sdk/blob/03a54353be9...