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Firefox always trys to open new windows in fullscreen but keeps them windowed on Mac

  • 5 replies
  • 1 has this problem
  • 18 views
  • Last reply by cor-el

TechnoSam
TechnoSam
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I just updated Firefox to the most recent version and I'm still having this problem. I'm on OSX 10.2.

When Firefox opens a new window, it thinks it's in full screen. It's not though. The result is that the "Close", "Maximize", and "Minimize" buttons in the corner are cut off and don't work. When I navigate to View > Exit Fullscreen, the window fixes itself.

I have no problem with Firefox opening in fullscreen mode. The problem is that it's not actually fullscreen. It just thinks that it is and compensates strangely. I've been through all the preferences of Firefox and all the settings of my Mac and I can't seem to find a solution for this. Does anyone have any help to offer? Thanks!

I just updated Firefox to the most recent version and I'm still having this problem. I'm on OSX 10.2. When Firefox opens a new window, it thinks it's in full screen. It's not though. The result is that the "Close", "Maximize", and "Minimize" buttons in the corner are cut off and don't work. When I navigate to View > Exit Fullscreen, the window fixes itself. I have no problem with Firefox opening in fullscreen mode. The problem is that it's not actually fullscreen. It just thinks that it is and compensates strangely. I've been through all the preferences of Firefox and all the settings of my Mac and I can't seem to find a solution for this. Does anyone have any help to offer? Thanks!

All Replies (5)

FredMcD
FredMcD
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You may have a corrupt xulstore.json file. https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved

TechnoSam
TechnoSam Question owner
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FredMcD said

You may have a corrupt xulstore.json file. https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved

I refreshed Firefox, but unfortunately, the issue persists. I meant to include an image in my original post, it looks like that didn't happen...

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Try to make the title bar visible via the button in the Customize palette.

  • "3-bar" Firefox menu button > Customize
  • View > Toolbars > Customize

You can toggle the title bar on/off via the "Title Bar" button at the bottom left in the Customize palette window.

TechnoSam
TechnoSam Question owner
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cor-el said

Try to make the title bar visible via the button in the Customize palette.
  • "3-bar" Firefox menu button > Customize
  • View > Toolbars > Customize
You can toggle the title bar on/off via the "Title Bar" button at the bottom left in the Customize palette window.

That seems to have fixed it! Thank you!

I wonder what causes that to happen though...

cor-el
cor-el
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  • Top 10 Contributor
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You're welcome.

This issue has been reported by others and that happens if the title bar is hidden.