How to Start Firefox in Safe Mode

This wikiHow teaches you how to restart Firefox on your computer into the browser’s built-in “Safe Mode”. This setting will disable all add-ons when Firefox starts. You can either restart Firefox into Safe Mode if the browser is open, or use a keyboard shortcut or command line program on your computer to force Firefox to open directly into Safe Mode. Note: you cannot start Firefox into Safe Mode on a smartphone or tablet.

Table of Contents

Start Firefox in Safe Mode

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Open Firefox. Click or double-click the Firefox app icon in the shape of an orange fox wrapped around a green globe.

If Firefox fails to open due to a problem and you need to start Firefox in Safe Mode, see the method for Windows or Mac, depending on your computer type.

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Click the ☰- shaped button in the upper-right corner of the Firefox page. A drop-down menu will appear.

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Click Help . This option is at the bottom of the drop-down menu.

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Click Restart with Add-ons Disabled . The option is at the top of the “Help” section of the drop-down menu.

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Click Restart when the option appears. Firefox will close.

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Click Start in Safe Mode when the option appears. Firefox will reopen in Safe Mode.

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Review browser performance. If Firefox’s problem no longer appears when opening in Safe Mode, it means that the cause lies in one or more add-ons you have installed.

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Disable add-ons if necessary. Go to the add-ons page by clicking the button , select Add-ons and click the Extensions tab, and then select Disable or Remove . ) to the right of an extension to disable or remove the option from Firefox.

You can also reset the entire browser to factory default settings by clicking Restart with Add-ons Disabled , selecting Refresh Firefox when the task appears, and clicking Refresh Firefox when prompted. again. This will delete all browser settings and add-ons.

Start Firefox in Safe Mode on Windows

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Try using keyboard shortcuts. In most cases, you can use a keyboard shortcut to start Firefox into Safe Mode. Look for the Firefox icon on your desktop, taskbar, or Start menu; Once found, you need:

Hold down the ⇧ Shift key.
Click or double-click the Firefox application icon.
Release the ⇧ Shift key when Firefox opens.
Click Start in Safe Mode when the option appears.
Troubleshoot Firefox if necessary.

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Open Start

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. Click the Windows icon in the lower left corner of the screen. A window will pop up.

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Open Command Prompt. You enter the command prompt and then click the . icon

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Command Prompt appears at the top of the Start window.

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Enter the command Firefox Safe Mode. Enter "C:Program FilesMozilla Firefoxfirefox.exe" -safe-mode into the Command Prompt.

If you installed Firefox in a different directory than the example above, try entering the command start firefox -safe-mode .

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Press ↵ Enter to execute the command.

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Click Start in Safe Mode when the option appears. This will confirm your choice and open Firefox in Safe Mode, at which point you can proceed to troubleshoot with the extension if necessary.

If you get an error or cannot start Firefox in Safe Mode, try entering the command "C:Program Files (x86)Mozilla Firefoxfirefox.exe" -safe-mode into the Command Prompt and press ↵ Enter .

Start Firefox in Safe Mode on Mac

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Try using keyboard shortcuts. In most cases, you can use a keyboard shortcut to start Firefox into Safe Mode. Look for the Firefox icon in the Applications folder, Dock, or Launchpad on your Mac, then:

Hold down the ⌥ Option key.
Click (or double-click) Firefox.
Release the ⌥ Option key when Firefox opens.
Click Start in Safe Mode when the option appears.
Troubleshoot Firefox if necessary.

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Open Spotlight

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. Click the magnifying glass icon in the upper right corner of the screen. A text frame will appear.