Mozilla Firefox/Firefox unresponsive


A few days ago my Firefox became unresponsive. It loaded (after 5 minutes) and froze. I did the uninstall and re-install and it worked on the relaunch, but after that it became unresponsive again. I did a troubleshoot compatibility on it and it says it wasn't compatible. What does any of this mean?

Hi Danny,

I'm very sorry for the delay in answering! Hopefully you have not given up on Firefox. I've recently have some issues in my personal life but I'm ready to answer.

Can you try to start Firefox in Safe Mode and see if it works fine? Usually slowness to Firefox can be caused by conflicting extensions. To get in Safe Mode, press the Help button (Firefox 29 has a new menu button dubbed "the pancake" button located at the right side of the navigational toolbar, click Help (?) and click "Restart with add-ons disabled". Once Firefox restarts, a dialog box will ask you what you want to do. Simply click "Start in Safe Mode". Browse in Safe Mode for about 20 minutes and see if it works. If it does, try to see if one of the extensions are causing it by going to your Add-ons list (Ctrl/Cmd + Shift + A) and disable your add-ons one by one to see if Firefox functions properly.

Another thing that helps is to disable Firefox's built in hardware acceleration. Firefox has hardware acceleration set to "on" by default, but it's still young, which means some video cards or drivers might have problems with it.

You might need to restart Firefox in order for this to take effect, so save all work first (e.g., mail you are composing, online documents you're editing, etc.).

Then perform these steps for Firefox version 29.0 and above:
1. Click the menu button [[Image:New Fx Menu]] and select Options for Windows or Preferences on Mac or Linux. For Firefox 28.0 and previous versions, click the orange Firefox button at the top left, then select the "Options" button, or, if there is no Firefox button at the top, go to Tools > Options.
2. In the Firefox options window, click the ''Advanced'' tab, then select "General".
3. In the settings list, you should find the ''Use hardware acceleration when available'' checkbox. Uncheck this checkbox.
4. Now, restart Firefox and see if the problems persist.

Additionally, please check for updates for your graphics driver by going to your graphics card distributor (Nvidia, AMD. Intel, etc).

Please let me know if this solves your issue. If not, we can continue troubleshooting.

Thank you VERY much for your patience while I've been dealing with family issues.

Mozilla Firefox

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Moses Bermea


I can answer almost any question about Firefox, add-on compatibility, how to force add-ons to work, browsing safely, about:config settings, flash problems. I can read Firefox crash reports and stop ads in Firefox.


I have been volunteering for Mozilla since January 2009 giving me 5 years of experience in both using Firefox, diagnosing problems, and giving correct fixes. I am currently a Moderator over at the Mozilla Support forums.

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