This wikiHow teaches you how to restart the computer version of the Firefox browser in Firefox's built-in "Safe Mode". Safe Mode will disable all add-ons when the browser is running. You can restart Firefox in Safe Mode once Firefox is opened. You can also use a computer keyboard shortcut (or a command line program) to force Firefox to open immediately in Safe Mode. Note that you cannot run Firefox in Safe Mode on a tablet or smartphone.
Step
Method 1 of 3: Restarting Firefox in Safe Mode
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Step 1. Start Firefox
Click or double-click the Firefox icon, which is a blue globe wrapped around an orange fox.
If Firefox won't open because of a problem that requires you to run it in Safe Mode, skip to the Mac or Windows method
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Step 2. Click in the top right corner of the Firefox page
A drop-down menu will be displayed.
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Step 3. Click Help
This option is at the bottom of the drop-down menu.
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Step 4. Click Restart with Add-ons Disabled
This option is in the top area of the " Help " section of the drop-down menu.
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Step 5. Click Restart when prompted
This action will close the Firefox browser.
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Step 6. Click Start in Safe Mode when prompted
Firefox will reopen in Safe Mode.
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Step 7. Check browser performance
If the problem you're having in Firefox goes away when you run it in Safe Mode, it means that one or more add-ons are causing the problem.
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Step 8. Turn off add-ons if necessary
Go to the add-ons page by clicking ☰, choose Add-ons, and click the tab Extensions. Next, click Disable or Remove on the right side of the add-on to turn it off or remove it from the Firefox browser.
You can also reset your browser to its default settings by clicking Restart with Add-ons Disabled, clicked Refresh Firefox when prompted, then clicks Refresh Firefox when asked to return. By doing this, all browser settings and add-ons will be removed.
Method 2 of 3: Running Firefox in Safe Mode on Windows Computer
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Step 1. Try using a keyboard shortcut
Usually you can use a keyboard shortcut to start Firefox in Safe Mode. Look for the Firefox icon on the desktop, taskbar, or Start menu. If you've found it, do the following:
- Hold down the Shift key.
- Click or double-click the Firefox icon.
- Release the Shift key when Firefox is open.
- Click Start in Safe Mode when requested.
- Fix issues in Firefox as needed.
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Step 2. Go to Start
Click the Windows logo in the lower left corner. A pop-up window will be displayed.
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Step 3. Run Command Prompt
Type command prompt, then click Command Prompt
at the top of the Start window.
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Step 4. Enter the Firefox Safe Mode command
Type "C:\Program Files\Mozilla Firefox\firefox.exe" -safe-mode into Command Prompt.
If you installed Firefox in a different folder than suggested, try typing start firefox -safe-mode
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Step 5. Press Enter key
The command you entered will be executed.
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Step 6. Click Start in Safe Mode when prompted
Your decision will be confirmed, and Firefox will open in Safe Mode, which you can use to fix plug-in issues as needed.
If you get an error message or you are not prompted to start Firefox in Safe Mode, try typing "C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -safe-mode into the Command Prompt, then press Enter
Method 3 of 3: Running Firefox in Safe Mode on Mac Computer
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Step 1. Try using a keyboard shortcut
Usually you can use a keyboard shortcut to start Firefox in Safe Mode. Look for the Firefox icon in your Mac's Applications folder, in the Dock, or in Launchpad. Next, do the following things:
- Hold down the Option key.
- Click (or double click) Firefox.
- Release the Option key when Firefox is open.
- Click Start in Safe Mode when requested.
- Fix problems in Firefox as needed.
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Step 2. Open Spotlight
Click the magnifying glass icon in the upper-right corner of the screen. This will bring up a text box.
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Step 3. Launch Terminal
Type terminal into Spotlight, then double click Terminal
in the list of displayed applications.
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Step 4. Enter the Firefox Safe Mode command
Type /Applications/Firefox.app/Contents/MacOS/firefox -safe-mode into Terminal.
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Step 5. Press Return
The command you entered will be executed.
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Step 6. Click Start in Safe Mode when prompted
Your decision will be confirmed, and Firefox will open in Safe Mode which you can use to fix plug-in issues as needed.