Diagnose Firefox issues using Troubleshoot Mode

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  • Revision id: 691
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  • Creator: Bo102010
  • Comment: Fix parenthesis
  • Reviewed: No
  • Ready for localization: Yes
  • Readied for localization by: AnonymousUser
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Safe Mode is a special Firefox execution mode that can be used to troubleshoot issues in Firefox. In Safe Mode, you can reset some settings or disable add-ons that might be the source of the issue. By comparing Firefox behavior in normal mode to its behavior in Safe Mode with various items disabled, you may be able to diagnose issues.

Note: Windows users may be familiar with a Safe Mode for Windows. Firefox Safe Mode has no connection to Windows Safe Mode.



How to start Firefox in Safe Mode

Click the menu button Fx89menuButton, click Help, select Troubleshoot Mode… and click Restart in the Restart Firefox in Troubleshoot Mode? dialog.

Note: You can also start Firefox in Troubleshoot Mode by holding down the Shift key while starting Firefox.holding down the option key while starting Firefox.quitting Firefox and then going to your Terminal and running: firefox -safe-mode
You may need to specify the Firefox installation path (e.g. /usr/lib/firefox).


Safe Mode window

93cafd5e0e8bef77b66875863ae7f197-1259888532-113-1.png You now have three options:

  • Clicking the Exit button cancels your attempt to get into Firefox's Safe Mode.
  • Clicking the Continue In Safe Mode button starts Firefox in its Safe Mode. While you are in Safe Mode, your extensions and themes will be disabled, and any toolbar customizations will be reverted back to their defaults. These changes are not permanent - when you leave Safe Mode and start Firefox up normally, your extensions, themes, and settings will return to the state they were in before you entered Safe Mode.
  • The Make Changes and Restart button is only enabled if you select one of the boxes above it.
Note: The following changes cannot be undone.

You can elect to make the following changes:

  • Disable all add-ons: If you select this box and then click Make Changes and Restart then Firefox will start back up in its normal mode, except all your extensions and themes (but not plugins) will be disabled (not uninstalled).
  • Reset toolbars and controls: If you select this box and then click Make Changes and Restart then Firefox will start back up in its normal mode, except any toolbar customizations you have made will be lost, such as position of buttons and toolbars.
  • Reset bookmarks to Firefox defaults: If you select this box and then click Make Changes and Restart then Firefox will delete your current bookmarks and replace them with its default set.
  • Reset all user preferences to Firefox defaults: If you select this box and then click Make Changes and Restart then any changes you have made to Firefox's options will be set back to their default settings.
  • Restore default search engines: If you select this box and then click Make Changes and Restart then any of the default search engines you deleted will be restored.

  • Disable all add-ons: If you select this box and then click Make Changes and Restart then Firefox will start back up in its normal mode, except all your extensions, themes, and plugins will be disabled (not uninstalled).
  • Reset toolbars and controls: If you select this box and then click Make Changes and Restart then Firefox will start back up in its normal mode, except any toolbar customizations you have made will be lost, such as position of buttons and toolbars.
  • Delete all bookmarks except for backups: If you select this box and then click Make Changes and Restart then Firefox will delete your current bookmarks and replace them with the default set (This item is labeled Reset bookmarks to Firefox defaults in Firefox 3.5).
  • Reset all user preferences to Firefox defaults: If you select this box and then click Make Changes and Restart then any changes you have made to Firefox's options will be set back to their default settings.
  • Restore default search engines: If you select this box and then click Make Changes and Restart then any of the default search engines you deleted will be restored.


Exiting Safe Mode

  1. Click the Firefox menu Fx89menuButton and select Exit.Click the Firefox menu at the top of the screen and select Quit Firefox.Click the Firefox menu Fx89menuButton and select Quit.
  2. Start Firefox as you normally would.




Based on information from Safe mode (mozillaZine KB)