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Firebox reverts to full-screen mode

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  • Last reply by cor-el

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I have to press the F11 key to see the menus, scroll bars, taskbar, etc but the screen then goes back to full-screen mode.

How do I prevent full-screen ?

I have to press the F11 key to see the menus, scroll bars, taskbar, etc but the screen then goes back to full-screen mode. How do I prevent full-screen ?

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Try to rename/remove xulstore.json in the Firefox profile folder with Firefox closed.

You can use the button on the "Help -> More Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page (Root directory).

Start Firefox in Troubleshoot Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration or if userChrome.css/userContent.css is causing the problem.

  • switch to the Default System theme: "3-bar" menu button or Tools -> Add-ons -> Themes
  • do NOT click the "Refresh Firefox" button on the Troubleshoot Mode start window