We got same problem, but with Mozilla Firefox. It's running latest update, but F-Secure wants to reboot all the time, because "Update pending" for Firefox.
Also running PSB 20.6, so does not seems like it's quite there yet.
Certain updates could trigger frequent reboot, including Mozilla Firefox and some windows updates. We’re still working on resolving the issue with windows updates.
For Firefox issue, It seems to be a bug in firefox:
So I would ask you to check if the latest Firefox 82.0.1 would not force a similar reboot cycle. There is some fix in FF 82.0.1.
And as a temporary solution: I would suggest excluding this patch from automatic installation ("PATCH = Mozilla Firefox").
Workaround is to exclude the problematic updates for the time being.