I’ve noticed somewhat-frequent ‘soft’ restarts. Typically it’s when I haven’t used the phone for awhile. I’ll pick up the phone, try to unlock with fingerprint, and it tells me something like “Cannot use the fingerprint login after restart”. Once I log in, all apps are closed.
It happens 1-2 times per day.
I didn’t see this listed as a symptom in the runaway thread problem currently being addressed, but maybe it’s related.