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Firefox crashed after I changed settings, I can't open Firefox back up to change the settings. Help!

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  • Last reply by FredMcD

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I tried to change my Firefox settings to delete my search form history and cookies. Then after it crashed. I have tried uninstalling and reinstalling, but Firefox still crashes. I read in the help section that I need to delete my profile from the Profile Manager, but I cannot get to it.

I tried to change my Firefox settings to delete my search form history and cookies. Then after it crashed. I have tried uninstalling and reinstalling, but Firefox still crashes. I read in the help section that I need to delete my profile from the Profile Manager, but I cannot get to it.

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First, try to start Firefox in Safe Mode. If that does not help,

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Use the Profile Manager to create and remove Firefox profiles

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Try Firefox Safe Mode to see if the problem goes away. Firefox Safe Mode is a troubleshooting mode that turns off some settings and disables most add-ons (extensions and themes).

(If you're using an added theme, switch to the Default theme.)

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu by clicking on the Restart with Add-ons Disabled... menu item:
FirefoxSafeMode

If Firefox is not running, you can start Firefox in Safe Mode as follows:

  • On Windows: Hold the Shift key when you open the Firefox desktop or Start menu shortcut.
  • On Mac: Hold the option key while starting Firefox.
  • On Linux: Quit Firefox, go to your Terminal and run firefox -safe-mode
    (you may need to specify the Firefox installation path e.g. /usr/lib/firefox)

Once you get the pop-up, just select "'Start in Safe Mode" Safe Mode Fx 15 - Win

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to find the cause.

To exit Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help others with the same problem.

Thank you.