I get CPU usage of 100%, fans running at full speed. My Junk directory contains no messages.
I also cannot change directories after that. (Should I make another issue for this?)
Logs from when I go to next directory: https://paste.debian.net/plainh/5b474c3a
Note: I get the same behavior without changing directory when the default directory is empty due to https://todo.sr.ht/~sircmpwn/aerc2/34.