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A small black rectangle appears in place of my minimize/close buttons and prevents these functions.

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  • 4 have this problem
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  • Last reply by cor-el

JillDolid
JillDolid
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The small black rectangle is just large enough to cover the minimize/resize and close buttons in the upper right corner of the screen. It appears after I have been using the browser for a while. In other words, it is not there when I first launch Firefox. I am able to close the window by using the task manager but not by clicking where the black rectangle is. Sometimes when I click all through the black triangle, it resizes the window somewhat but not consistently.

The small black rectangle is just large enough to cover the minimize/resize and close buttons in the upper right corner of the screen. It appears after I have been using the browser for a while. In other words, it is not there when I first launch Firefox. I am able to close the window by using the task manager but not by clicking where the black rectangle is. Sometimes when I click all through the black triangle, it resizes the window somewhat but not consistently.

All Replies (1)

cor-el
cor-el
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  • Top 10 Contributor
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Start Firefox in Diagnose Firefox issues using Troubleshoot Mode to check if one of the extensions is causing the problem (switch to the DEFAULT theme: Firefox (Tools) > Add-ons > Appearance/Themes).

In Firefox 4 and later Safe mode disables extensions and disables hardware acceleration. Try to disable hardware acceleration.

  • Tools > Options > Advanced > General > Browsing: "Use hardware acceleration when available"

If disabling hardware acceleration works then check if there is an update available for your graphics display driver.