If I can give a bit more information on this bug, since it affects me too...
Every day, at around the same time, I notice my computer heating up, because the unattended-upgrades process is running. This happens even though I have masked the service in systemd. Attempting to kill the process does not work unless I do `kill -9`, even then it immediately respawns unless I also stop the process in systemd. This is on a fairly clean bullseye install.
