When I open Firefox docs in my email, I get so many repeating windows my Mac freezes
On occasion I get an attachment in my email that opens with Firefox. As soon as I open the attachment my screen suddenly goes crazy with repeated blank windows. They cannot be stopped and the computer freezes up so I have to reboot. I do not have this problem with attachments that do not use Firefox to open.
Wšykne wótegrona (2)
What are you calling "Firefox docs"? That can happen when you have Firefox set to open file types it doesn't handle normally, like Word .doc files or PDF files.