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Top and bottom of FireFox window disappear in seconds (the window expands too far). All other windows operate normally. Now what? I've uninstalled and reinsta

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I was using Firefox for a few years with great enjoyment. Recently I opened it and within a second or so, it enlarged to the point that the top and bottom of the screen expanded off the screen. No other windows in any other program are doing this. The only way to close it is by using the task manager. Very frustrated. What other info do you need?

I was using Firefox for a few years with great enjoyment. Recently I opened it and within a second or so, it enlarged to the point that the top and bottom of the screen expanded off the screen. No other windows in any other program are doing this. The only way to close it is by using the task manager. Very frustrated. What other info do you need?

All Replies (6)

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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.

Did this fix your problems? Please report back to us!

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Nope. I uninstalled and reinstalled and it still does it. Can't even get to the top bar to close it.

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Can't get to the Help>Troubleshooting

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My screen resolution is the recommended 1280X1024. Nothing else does this.

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Hi ConnieHampton, FIrefox will remember the last window size you had, which is why it keeps opening too large each time you open and close it. To fix this, try resetting Firefox: https://support.mozilla.org/en-US/kb/changes-toolbars-and-window-sizes-are-not-saved?esab=a&s=resize+window&r=7&as=s

If you don't see your menu bar, you may be in full screen mode, and can turn it off by following these instructions: https://support.mozilla.org/en-US/kb/how-make-firefox-and-websites-go-full-screen?esab=a&s=full+screen&r=0&as=s

If this doesn't work, please let us know and we'll figure out another way to fix it.

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Thank you, that did it.