I see it crashing sometimes when the phone screen has been off (and android q forces system & apps into low-performance mode), or the app gone to the background but still running.
I just close the app and restart. there was this one time where restarting would crash it, but that fixed itself after a cache-wipe from system settings.

Having programmed a bit on ssb-clients myself now I really really appreciate the subtle and good design of the Manyverse app. hats off to you @andré and CO for such an amazing app!