Firefox Bad Behaviour in Linux


Firefox has been widely deployed in various Linux distributions and Mac OS X. Recently, it has been the default browser for most Linux distributions. Most of the web-based applications claimed to be well tested in Firefox. Thus, it is supposed that firefox is a standard browser. However, it may sometimes go wrong for accessing several webpages with bad behaviours after working healthily for a period of time.


If some of the bad behaviours happen in Firefox like the case that the display refreshes so slow or even stalled such that some of the fonts or images either disappear or displayed stranagely.

If you are desparate with the situation that there is no solution on this issue on the web or even no similar issue posted, or already tried something like running Firefox in “safe mode” to troubleshoot the problem. Then the following may be a cure to the problem described below.


  1. In case you find that your firefox works properly by other users in your machine. In case only one non-root user is created, then it is not bad to try using root user to check the firefox behaviour. If it works properly under other users, then the issue may be all about bad user profile of firefox. You can copy and replace the firefox user profile of bad behaviour by that of the good behaviour using root access.
  2. The profile directory is located in ~/.mozilla/firefox/
  3. Either change the profile directory name after copying or just modify the content of the profile.ini file.
  4. If you are heavily using firefox as default browser, in the long-term, I suggest that you back up your firefox user profile of the good behaviour.


  1. If you have not installed any Add-ons or extension to your firefox, then probably restarting in “safe mode” does not help.
  2. If guessing the Firefox goes too slow to trigger the bad behaviours and suggested by disabling “hardware acceleration“, in this case, this action does not help.
  3. Re-installing firefox will not remove the bad firefox user profile residing in “/home/[user]/.mozilla/firefox” directory. It must be removed or replaced by a good profile manually. Though my case happened in openSUSE, I am quite sure it will happen in other Linux distributions, and the cure is similar to the above.


  • openSUSE 12.3
  • Firefox 19.0.2 (openSUSE branded)