In 13.04 FireFox was working just fine, but after the upgrade, every few minutes, FireFox locks up and eventually changes to that dreaded "grayscale window" for several seconds.

The problem appeared immediately after the upgrade. I'm afraid I don't know which version I had before the upgrade, but now I am running FireFox 24.0.

Is this a known bug, or are there any steps I can take to find the root cause?


I tried disabling all my add-ons, and the problem went away. Re-enabling them one at a time, I found that Ubuntu FireFox Modifications 2.8 was causing the performance issues. That add-on wasn't installed by me, but must have been added automatically with the upgrade.

If anyone else runs into the issue, go to the Tools menu and click Add-ons. Scroll down in the list until you find Ubuntu FireFox Modifications, and click the Disable button (may require a restart to take effect).

| improve this answer | |
  • Originally I didn't think add-ons would be the cause of the issue, as I didn't install any new ones manually after the upgrade, and my existing list of add-ons is already spartan. – IQAndreas Oct 21 '13 at 23:52
  • Disabling the Firefox modifications didn't get rid of the problem for me, in fact, it appears as though Firefox is the canary in the mine, it happens elsewhere also but Firefox shows it up quickly likely because I use it a lot. – user212365 Nov 7 '13 at 14:21
  • 1
    I was right on the cusp of moving my Firefox profile onto a USB stick and throwing it into the sea. You've just saved me a USB stick and a long drive. Thank you. – Oli Dec 1 '13 at 13:37

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.