Well, I'm back. My former laptop heard that I had a tax refund coming and promptly fried out its CPU.
I realize it's illogical to attribute motives to inanimate technology, but dang, it sure felt malicious. On the other hand, Firefox deleting all my passwords just because I had to reset the main one, is sheer human idiocy. Is it possible that someone else was trying to reset my password? Remotely, yes. That's why the link is sent to my personal email, so I would know if an attempt is being made to reset it without my authorization, and I could stop it. Security is security, but this is just paranoia. What makes it worse was finding the file with the password 5 minutes later, and having no link to contact Firefox and ask if they can undo the process somehow, or give me back my other passwords. I mean, I'm me. I should know.