thanks, I'll try it too, and had long been looking for a solution andcould not find it anywhere.
My flash has still been crashing, it's getting to be a real bother now XD
I was also facing same issue frequently.
I did update to latest firefox 16.0.2 and Latest flash 11.3
But nothing could help me.
There is problem in flash not firefox.
I just downgrade my flash to 10.3 (installed only plugin - 3MB only not full player)
I follwed article on official mozilla page here http://goo.gl/1gslj
I always want to keep all apps up to date but no choice here/
I will update my flash after a month and will see if the issue is resolved or not in any future release.