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An annoying grey box with the text "100%" is displaying on all of my Firefox screens. I do not know what this is or how to remove. Any ideas? thank you.

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This box appeared on 1/31/11, I believe. I cannot move it by clicking and dragging, and a right click does not display any additional info. I've goggled around and not found any references to it either. The box is displayed in the upper left quadrant of the screen.

This box appeared on 1/31/11, I believe. I cannot move it by clicking and dragging, and a right click does not display any additional info. I've goggled around and not found any references to it either. The box is displayed in the upper left quadrant of the screen.

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Do you have that problem when running in the Firefox SafeMode?
http://support.mozilla.com/en-US/kb/Safe+Mode
Don't select anything right now, just use "Continue in SafeMode."

If not, see this:
http://support.mozilla.com/en-US/kb/troubleshooting+extensions+and+theme...

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Your above posted system details show outdated plugin(s) with known security and stability risks that you should update.

  • Next Generation Java Plug-in 1.6.0_17 for Mozilla browsers

Update the Java plugin to the latest version.

You may also have to check http://kb.mozillazine.org/Java#Multiple_Java_Console_extensions


Do a malware check with some malware scan programs.
You need to scan with all programs because each program detects different malware.
Make sure that you update each program to get the latest version of the database before doing a scan.

See also "Spyware on Windows": http://kb.mozillazine.org/Popups_not_blocked and What to do when searches take you to the wrong search website