Reset Firefox preferences to troubleshoot and fix problems
Revision Information
- Revision id: 36866
- Created:
- Creator: Jan.
- Comment: keep previous instructions for ff 2 to ff 12, fixed FOR version mismatch. prefs.js for ff15+
- Reviewed: No
- Ready for localization: No
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Revision Content
Resetting preferences (zoom, tabs, privacy, network, encryption, download actions, etc.) is one of many procedures that can be helpful in fixing Firefox issues. This has been simplified in the latest version of Firefox. Now you can restore Firefox to its factory default state while saving your essential information.
- Click the menu button , click and select .
- Click then in the confirmation window that opens. Firefox will close to refresh itself.
- When finished, a window will list your imported information. Click the button. Firefox will open.
- Select whether you want Firefox to restore all or some windows and tabs and click the button.
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:
Click the menu button , click
, select and click in the Restart Firefox in Troubleshoot Mode? dialog.firefox -safe-mode
You 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.
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 reset preferences by either removing the preferences files.
How to reset preferences to default
- Exit Firefox completely (if open).
- Open the Firefox profile folder.
- Delete (or rename) the prefs.js file. Warning: If you find more than one prefs.js file or a "prefs.js.moztmp" file, delete these files as well and read How to fix preferences that won't save.
- Delete the user.js file, if found, or move it to a backup location (this file does not exist by default).