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fullscreen is tiny in upper left corner

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  • 16 have this problem
  • 8 views
  • Last reply by cor-el

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whenever i hit F11 or click a 'fullscreen' button (ie facebook image, vimeo video, youtube etc) firefox disappears into a box sized 320x180 px in upper left corner.

whenever i hit F11 or click a 'fullscreen' button (ie facebook image, vimeo video, youtube etc) firefox disappears into a box sized 320x180 px in upper left corner.

Chosen solution

You can try to rename/remove xulstore.json and if present delete localstore.rdf in the Firefox profile folder with Firefox closed.

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


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

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window
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Chosen Solution

You can try to rename/remove xulstore.json and if present delete localstore.rdf in the Firefox profile folder with Firefox closed.

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


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

  • switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
  • do NOT click the "Refresh Firefox" button on the Safe Mode start window