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A blank gray box won't go away...why not? How can I get rid of it?

  • 3 replies
  • 2 have this problem
  • 4 views
  • Last reply by lmahovetz

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Every time I open Firefox, a gray box (about 1in x 1in) appears in the near upper left hand corner of my screen. When Firefox is open (and not hidden) the gray square covers any window that it is located over - this will included any non-Firefox applications. Only when Firefox is exited or hid will the gray square disappear. Please help!! I'd like this square to be gone.

Every time I open Firefox, a gray box (about 1in x 1in) appears in the near upper left hand corner of my screen. When Firefox is open (and not hidden) the gray square covers any window that it is located over - this will included any non-Firefox applications. Only when Firefox is exited or hid will the gray square disappear. Please help!! I'd like this square to be gone.

All Replies (3)

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This could be a feature of a Firefox add-on. A standard diagnostic to bypass interference by extensions (and some custom settings) is to try Firefox's Safe Mode.

First, I recommend backing up your Firefox settings in case something goes wrong. See Back up and restore information in Firefox profiles. (You can copy your entire Firefox profile folder somewhere outside of the Mozilla folder.)

Next, restart Firefox in Firefox's Safe Mode (Diagnose Firefox issues using Troubleshoot Mode) using

Help > Restart with Add-ons Disabled

In the dialog, click "Start in Safe Mode."

If the site works correctly, this points to one of your extensions or custom settings as the problem.

To further disable add-ons, you can try here:

Tools > Add-ons > Plugins category

Any change?

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You can also try to remove the Firefox plist file (org.mozilla.firefox.plist).

Go to "~/Library/Preferences" and remove the plist file for Firefox (org.mozilla.firefox.plist)


You can also check for problems with the localstore.rdf file.

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Yes it worked thank you!!! I found the add-on that was triggering it and disabled it!