I always try to search the forum before posting, although it isn't always easy to guess the right key words, especially as phrases (as in Google advanced) or Boolean operators are not allowed.
I just updated both FF and TB and had to fiddle around as usual. Also the method I find seems to be different each time - sometimes because of Mozilla changes, and because there's more than one way to kill this particular cat. Still, it's done for now.
I wonder if the new flash version will still crash after 6+ hours - tell you tomorrow!