I find it hard to find that firefox is causing this - but for the ones that think it's the cause, can you please go to Preferences -> Advanced -> General Tab and disable / enable hardware acceleration to see if that could be the cause?
In this thread there seems to be different things at stake. On my case, the crashes stopped by setting i915.i915_enable_rc6=0 i915.i915_enable_fbc=0 in grub, and I'm a heavy user of firefox -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/993187 Title: ubuntu 12.04 completely freezes frequently. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/993187/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs