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Firefox doesn't automatically open in full screen

cor-el replied
arbrus

Firefox doesn't automatically open in full screen anymore. I don't think I did anything for this to happen all of a sudden. It always opens now in a small screen in upper left corner. I have to click on the little double square symbol, then on the full screen square symbol to get a full screen.

Firefox doesn't automatically open in full screen anymore. I don't think I did anything for this to happen all of a sudden. It always opens now in a small screen in upper left corner. I have to click on the little double square symbol, then on the full screen square symbol to get a full screen.

All Replies (1)

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).