Very soon after startup it begins to stutter with the spinning beachball of unresponsiveness. At first it will spin, then come back for a few seconds, then spin again. Eventually the whole app is unresponsive. The troubleshooting steps I see on here all start with "Go to [some location in the menu]". I can't do anything with anything in Thunderbird. I can force it to quit and start it up again, that's about it. It is also always asking me for the passwords of some of my IMAP accounts. These are big accounts, some folders have several hundred thousand emails. The Inboxes are smaller, maybe a couple hundred in total at the moment. The last configuration I was able to make put it into Unified mode. The damn thing is that after having been useless like this ever since I installed it, last week it started to work fine. Stayed that way for several days. Eventually that failed, though, and my whole Mac ended up locked up the way the app is, I had to manually power it off. I don't know if it writes any info about what it's doing to a log file somewhere, I am not having much luck trying to find any information here. Just other people with similar problems but no substantive replies. Using Thunderbird on an older Mac laptop, running macOS Monterey 12.7.5.