No, I haven't. I have Tree Style Tab and just a few days ago I installed Easy Copy. The other 4 are Ubuntu related (2x Ubuntu, 2x Unity). Also no Flash (yet).
It wouldn't surprise me if this is somehow a Ubuntu 14.04 thing. I used Firefox on Ubuntu 10.04 until very recent and if it crashed it was most of the time (maybe even each time) Flash related. On 14.04 Firefox crashes about once a day. Sometimes out of the blue (i.e. editing in Emacs, or when I move the mouse to wake up the monitor).
I've read some of the bug reports associated with the crashes I have, and some are marked as being in the top n of crashes (see my earlier post). So (to me) they seem to be genuine crashes, which maybe show up more often on Ubuntu 14.04. Aside: Ubuntu 14.04 has plenty of stability issues of its own; several crash reports/day. And no, I don't think the hardware I use suddenly went bad after I installed 14.04. And since I am paranoid I did run memtest for hours.
Note that I can not always be bothered to actually submit the crashes. Some of those crashes are marked as "top crashes", see also my earlier post.
*Sigh* what's with this blame the add-on stuff? I see it in each and every "Firefox crashes" discussion. Until recently I used Firefox (can't recall which version, the latest supported) on Ubuntu 10.04. Crashes were rare and mostly related to Flash content. Now I am on Ubuntu 14.04 and Firefox crashes several times a day. Often randomly, like when I am editing code in Emacs. Or when I have been away from the computer for a while and I move my mouse to wake up the monitor.
Some clicking on about:crashes links gives the following:
So, yeah, there's plenty of work to do. Would be nice if this stuff gets a higher priority and let the eye candy / let's make it look like Chrome even more rest for a year... or two.
Everything should be made as simple as possible, but not simpler. -- Albert Einstein