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I have 3 small lines on window next to red close button, anyone else got this problem

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

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I have 3 small lines on window next to red close button only about 3mm long they are from the corner of the left hand side of the window and go towards the red close button. Any ideas?

I have 3 small lines on window next to red close button only about 3mm long they are from the corner of the left hand side of the window and go towards the red close button. Any ideas?

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I remember having seen this issue reported before, but haven't made a note of it.

Does that icon have a tooltip if you hover it?

Which effect does it have if you click the icon (if possible)?

It is either added by a Firefox extension or by other software that is installed on your computer.


Start Firefox in Safe 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).