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After viewing YouTube video full screen on secondary monitor, new windows always open secondary monitor *not* main monitor.

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  • 最後の返信者: cor-el

As the question. This is a problem that persists through restarts and reboots.

I've had this problem before in previous versions of Firefox, but could correct it by viewing a YouTube hosted video full-screen on the main monitor, close the window then restart FF, then new windows would once again open on the main monitor. Unfortunately this quick fix no longer appears to work.

I've tried disabling all add-ons and then restarting FF, but the same behaviour happens.

As the question. This is a problem that persists through restarts and reboots. I've had this problem before in previous versions of Firefox, but could correct it by viewing a YouTube hosted video full-screen on the main monitor, close the window then restart FF, then new windows would once again open on the main monitor. Unfortunately this quick fix no longer appears to work. I've tried disabling all add-ons and then restarting FF, but the same behaviour happens.

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The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information. Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

  1. Go to Firefox > Help > Troubleshooting Information.
  2. Click the "Reset Firefox" button.
  3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
  4. Firefox will open with all factory defaults applied.


Further information can be found in the Refresh Firefox - reset add-ons and settings article.

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