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A weird glitch keeps appearing in the upper left corner, is this normal?

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  • Last reply by cor-el

Usathecat
Usathecat
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I keep having a weird glitch appear in the upper left hand corner of my firefox window. It appears right over the exit,minimize, and expand buttons. I don't know if this means if got a virus or something, but its quite strange and only happens with firefox.

I keep having a weird glitch appear in the upper left hand corner of my firefox window. It appears right over the exit,minimize, and expand buttons. I don't know if this means if got a virus or something, but its quite strange and only happens with firefox.

All Replies (1)

cor-el
cor-el
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  • Top 10 Contributor
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Start Firefox in Safe Mode to check if one of the extensions (Firefox menu button/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: Firefox menu button/Tools > Add-ons > Appearance
  • Do NOT click the Reset button on the Safe Mode start window

Try to set browser.tabs.drawInTitlebar to false on the about:config page to disable displaying the tabs in the title bar.

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.