UPDATE – Not Firefox but another dodgy logic board. See this post.
Of late, my Powerbook has been crashing to a “grey screen of death” (you know the one with the overlay on the screen) or just freezing. Many, many reboots have ensued, accompanied by profuse swearing. Occasionally, what I’m assuming is the leftover pollution from the crash causes another crash on startup. More swearing.
I’ve pretty much singled out Firefox (or at least Firefox and a combination of one or more extensions) as the culprit. Be damned if I can single out which of the little buggers it might be, although I strongly suspect FlashGot.
I’m about to go through another cycle of disabling and progressively re-enabling my (20-odd) extensions as I try to figure out which extension is to blame. My kingdom for better memory management in these things!