Troubleshoot Firefox issues using Safe Mode
Safe Mode is a special Firefox mode that can be used to troubleshoot and fix problems. Safe Mode temporarily turns off hardware acceleration, resets some settings, and disables add-ons (extensions and themes) that might be causing problems. By comparing Firefox behavior in normal mode to its behavior in Safe Mode you may be able to pinpoint the cause of the problem.
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How to start Firefox in Safe Mode
Click the menu button , click help and select. Firefox will start up with the Firefox Safe Mode dialog.
You may need to specify the Firefox installation path (e.g. /usr/lib/firefox)
Safe Mode window
You now have two options:
- Clicking the button will temporarily disable your extensions and themes, turn off hardware acceleration and reset toolbar and button customizations. 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.
- Clicking the Refresh Firefox - reset add-ons and settings for more information about this option. button will restore Firefox to its factory default state while saving your essential information. See
Troubleshooting problems in Safe Mode
Once Firefox is in Safe Mode, you'll want to test its behavior and see if the problem goes away.
The problem happens in Safe Mode
If the problem still happens in Safe Mode, it is not being caused by an extension or theme. Other possible causes could be plugins or changes made to Firefox preference settings, which are not disabled in Safe Mode. See the following articles for solution:
- Troubleshoot and diagnose Firefox problems
- Troubleshoot issues with plugins like Flash or Java to fix common Firefox problems
- Reset Firefox preferences to troubleshoot and fix problems
The problem does not happen in Safe Mode
If the problem does not happen in Safe Mode, it is most likely because of an extension, theme or hardware acceleration.
- See the article Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems for solutions.
Exiting Safe Mode
- Click the menu button and then click ExitQuit .
- Start Firefox as you normally would.
- If Firefox keeps starting in Safe Mode, see Firefox is stuck in Safe Mode.
Based on information from Safe mode (mozillaZine KB)