This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

When I move my cursor around in firefox, whatever it moves over is then blocked out with dark shapes and lines. How do I fix this?

  • 1 reply
  • 1 has this problem
  • 5 views
  • Last reply by cor-el

more options

When I open firefox, the whole screen with google homepage would flick up then it would suddenly be blocked by the whole screen filling in with a dark background and lots of white lines patterning over the screen. I removed firefox and then reinstalled and now the same patterns appear when I move my cursor over the tool bar and anywhere there is writing. I have checked and I don't have any virus's. How do I fix this? Raemer

When I open firefox, the whole screen with google homepage would flick up then it would suddenly be blocked by the whole screen filling in with a dark background and lots of white lines patterning over the screen. I removed firefox and then reinstalled and now the same patterns appear when I move my cursor over the tool bar and anywhere there is writing. I have checked and I don't have any virus's. How do I fix this? Raemer

All Replies (1)

more options

Start Firefox in Safe Mode to check if one of the extensions (Firefox/Tools > Add-ons > Extensions) or if hardware acceleration is causing the problem (switch to the DEFAULT theme: Firefox/Tools > Add-ons > Appearance).

  • Do not click the Reset button on the Safe mode start window or otherwise make changes.

Try to disable hardware acceleration in Firefox.

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