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Firefox unmaximizes itself when switching tabs in task bar

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  • Last reply by guigs

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When switching tabs using the windows taskbar during an extended online session spanning multiple tabs and windows, the window will unmaximize itself. Switching tabs using the physical tab works correctly. This only occurs with the "Show tabs preview in the Windows Taskbar" opton enabled. Closing all open firefox windows and restarting firefox is the only fix I have found.

When switching tabs using the windows taskbar during an extended online session spanning multiple tabs and windows, the window will unmaximize itself. Switching tabs using the physical tab works correctly. This only occurs with the "Show tabs preview in the Windows Taskbar" opton enabled. Closing all open firefox windows and restarting firefox is the only fix I have found.

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Hi achenbachs630420, This is expected behavior for the Windows 7 operating system. However when I have Firefox in fill screen mode for a window and hover over the taskbar the preview will show up and the full screen will remain, and I have the same feature selected, weird?

Try Firefox Safe Mode to see if the problem goes away. Firefox Safe Mode is a troubleshooting mode that turns off some settings, disables most add-ons (extensions and themes).

If Firefox is open, you can restart in Firefox Safe Mode from the Help menu:

  • In Firefox 29.0 and above, click the menu button New Fx Menu, click Help Help-29 and select Restart with Add-ons Disabled.
  • In previous Firefox versions, click on the Firefox button at the top left of the Firefox window and click on Help (or click on Help in the Menu bar, if you don't have a Firefox button) then click on Restart with Add-ons Disabled.

If Firefox is not running, you can start Firefox in Safe Mode as follows:

  • On Windows: Hold the Shift key when you open the Firefox desktop or Start menu shortcut.
  • On Mac: Hold the option key while starting Firefox.
  • On Linux: Quit Firefox, go to your Terminal and run firefox -safe-mode
    (you may need to specify the Firefox installation path e.g. /usr/lib/firefox)

When the Firefox Safe Mode window appears, select "Start in Safe Mode".
Safe Mode Fx 15 - Win

If the issue is not present in Firefox Safe Mode, your problem is probably caused by an extension, and you need to figure out which one. Please follow the Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems article to find the cause.

To exit Firefox Safe Mode, just close Firefox and wait a few seconds before opening Firefox for normal use again.

When you figure out what's causing your issues, please let us know. It might help others with the same problem.