Reset Firefox preferences to troubleshoot and fix problems
When troubleshooting Firefox problems, resetting preferences (zoom, tabs, privacy, network, encryption, download actions, etc.) is one of many procedures that can be helpful in pinpointing the issue. This article explains how to use Safe Mode to reset preferences.
- If changes to preference settings are not saved when you restart Firefox, see How to fix preferences that won't save.
To reset preferences: At the top of the Firefox window, click the button, go over to the menuOn the menu bar, click the menuAt the top of the Firefox window, click the menu and select . Firefox will start up with the Firefox Safe Mode dialog.
firefox -safe-modeYou may need to specify the Firefox installation path (e.g. /usr/lib/firefox)
- Click to put a check mark by Reset all user preferences to Firefox defaults.
- To apply your changes, click .
Firefox will restart with your preference settings changed back to the defaults.
Resetting preferences (zoom, tabs, privacy, network, encryption, download actions, etc.) is one of many procedures that can be helpful in fixing Firefox issues. There are two ways to do this - reset Firefox to it's default state or delete the preference files. We'll explain both methods.
- If changes to preference settings are not saved when you restart Firefox, see How to fix preferences that won't save.
Table of Contents
Solution 1: Reset Firefox to its default state
- At the top of the Firefox window, click the menu and select .
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- Click the button in the upper-right corner of the Troubleshooting Information page.
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- To continue, click in the confirmation window that opens.
- Firefox will close and be reset. When it's done, a window will list the information that was imported. Click and Firefox will open.
- At the top of the Firefox window, click the button, go over to the sub-menu
and select . -
- Click the button in the upper-right corner of the Troubleshooting Information page.
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- To continue, click in the confirmation window that opens.
- Firefox will close and be reset. When it's done, a window will list the information that was imported. Click and Firefox will open.
- On the menu bar, click the menu and select .
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- Click the button in the upper-right corner of the Troubleshooting Information page.
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- To continue, click in the confirmation sheet that slides down.
- Firefox will close and be reset. When it's done, a window will list the information that was imported. Click and Firefox will open.
- At the top of the Firefox window, click the menu and select .
-
- Click the button in the upper-right corner of the Troubleshooting Information page.
-
- To continue, click in the confirmation window that opens.
- Firefox will close and be reset. When it's done, a window will list the information that was imported. Click and Firefox will open.
Solution 2: Delete Firefox preference files
At the top of the Firefox window, click the button, go over to the menuOn the menu bar, click the menuAt the top of the Firefox window, click the menu and select . Firefox will start up with the Firefox Safe Mode dialog.
firefox -safe-modeYou may need to specify the Firefox installation path (e.g. /usr/lib/firefox)
- Click to put a check mark by Reset all user preferences to Firefox defaults.
- To apply your changes, click .
Firefox will restart with your preference settings changed back to the defaults.
At the top of the Firefox window, click on the button, go over to the menuOn the menu bar, click on the menuAt the top of the Firefox window, click on the menu and select . The Troubleshooting Information tab will open.
- Under the Application Basics section, click on . A window with your profile filesfolder will open.
- At the top of the Firefox window, click on the button and then select At the top of the Firefox window, click on the menu and then select On the menu bar, click on the menu and select At the top of the Firefox window, click on the menu and select
- Locate and delete the prefs.js file. If you find more than one, a prefs.js.moztmp file or a user.js file, delete these as well.
- You can close the profile folder and open Firefox now.
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