This might seem like a nit-pick, since it works fine otherwise, but this is getting to me.
If I close Firefox, it appears to shut down just fine. Until next run, where it's just like it had crashed, offering to restore the last tab set.
Restarting is similar - except Firefox never re-launches. It just closes down.
I thought maybe running it from the terminal might solve the problem, but instead I get a backtrace... which means absolutely nothing to me. If you want to try and decipher it, have a look here:
http://pastie.org/2125802
This Firefox is running on a 32-bit Gentoo Linux, compiled with the 'debug' USE flag, and without the 'custom-optimisation' flag (as it's not safe, AFAIK).
Tried running it in safe-mode to eliminate any addon induced problems, but unfortunately no difference in the slightest.
I know, it's a small thing really.