I have exactly the same problem. In my case, firefox crashed when it was executed on vnc4server with a resolution of 2560x1600, 16bit color depth. Firefox segfaulted on a smaller resolution (1024x768), too.
As a sidenote, ~/.vnc/xstartup was:
unset SESSION_MANAGER . /etc/X11/Xsession
which launched the default gnome desktop.
I have exactly the same problem. In my case, firefox crashed when it was executed on vnc4server with a resolution of 2560x1600, 16bit color depth. Firefox segfaulted on a smaller resolution (1024x768), too.
As a sidenote, ~/.vnc/xstartup was:
unset SESSION_MANAGER
. /etc/X11/Xsession
which launched the default gnome desktop.