Steps to close and restart Firefox:

• To begin, launch Mozilla Firefox. Type about: profiles into the address bar and press Enter (or Return on Mac).
• Locate the option labelled 'Restart' in the upper-right corner of the 'About Profiles' page that appears. Click 'Restart Normally' to restart the browser while keeping all of your open tabs.
• Firefox will shut down and restart as if you had chosen 'Exit' or 'Quit Firefox' from the main Firefox menu. Firefox, on the other hand, will reopen all of your tabs after it restarts.
• Return to the about: profiles page and click 'Restart With Add-ons Disabled' if you need to troubleshoot troublesome add-ons. You'll get a pop-up warning message about starting Firefox in Troubleshoot Mode after clicking. There are two possibilities available here.
• You can refresh Firefox by clicking 'Refresh Firefox,' which removes your add-ons and returns it to its default configuration. This is a harsh measure that should only be taken as a last resort. Your add-ons and settings will be lost.
• Otherwise, you can use Troubleshoot Mode to temporarily disable your extensions and customizations. Nothing will be changed or removed permanently. Click 'Open' to do so.
• Your customizations and add-ons will be disabled when Firefox closes and restarts. Close all Firefox windows and restart the app to re-enable them, or go to about : profiles and click 'Restart Normally.'

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