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When I scroll in Firefox, a line of distortion shows up horizontally across the page. It happens in no other applications.

  • 3 replies
  • 10 have this problem
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  • Last reply by cor-el

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When I scroll in Firefox, a feint but noticeable line of distortion (directly in line with where my cursor is grabbing and dragging the scroll bar) shows up horizontally across the page in many Firefox windows. It happens in no other applications. Mac OS X 10.7, Lion on a Mac Mini Server, 2011. Any suggestions or files I ought to remove to make this go away?

When I scroll in Firefox, a feint but noticeable line of distortion (directly in line with where my cursor is grabbing and dragging the scroll bar) shows up horizontally across the page in many Firefox windows. It happens in no other applications. Mac OS X 10.7, Lion on a Mac Mini Server, 2011. Any suggestions or files I ought to remove to make this go away?

Modified by earthman7

Chosen solution

You're welcome

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Try to disable hardware acceleration.

  • Firefox > Preferences > Advanced > General > Browsing: "Use hardware acceleration when available"

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

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Try to disable hardware acceleration. Firefox > Preferences > Advanced > General > Browsing: "Use hardware acceleration when available"

The simple instructions above did it!!! I didn't understand the other instructions you gave about Safe Mode, but didn't need that anyway.

Thanks for your help!

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Chosen Solution

You're welcome