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Blinking vertical lines in tab bar?

  • 3 replies
  • 35 have this problem
  • 11 views
  • Last reply by M.G.

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There are small vertical lines in the tab bar. They appear after closing tabs. They blink and change places when I hover the cursor over any Firefox buttons or bars. And sometimes they start to blink and mirror the text cursor in the address bar.

Disabling all add-ons and themes does not affect them.

I'll try to add a screenshot of the problem.

There are small vertical lines in the tab bar. They appear after closing tabs. They blink and change places when I hover the cursor over any Firefox buttons or bars. And sometimes they start to blink and mirror the text cursor in the address bar. Disabling all add-ons and themes does not affect them. I'll try to add a screenshot of the problem.

Chosen solution

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
Read this answer in context 👍 3

All Replies (3)

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Here is a screenshot

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Chosen Solution

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
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It was the hardware acceleration.

Thank you cor-el!