Comment 1 for bug 1284103

"Please don't assume that everybody else will be able to reproduce your crash, just because you experience the issue. All crash reports must be submitted with a complete stacktrace and a description of the steps required to trigger the crash (if it is reproducible). Bug reports which tell us that the application crashes without any other technical information about the crash (ie, a complete stacktrace) are not very useful. "

Try running FIrefox in safe mode: https://wiki.ubuntu.com/MozillaTeam/Bugs#Try_running_in_safe_mode

If it's still crashing, then see procedure here: https://wiki.ubuntu.com/MozillaTeam/Bugs#Crashes