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There is a whitish rectangle displayed on the top left hand side of my display in 4K

  • 5 replies
  • 1 has this problem
  • 9 views
  • Last reply by James

Louwin
Louwin
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As my question title says....

I have just attached a 4K 3840X2160 TV as a monitor and this whitish overlay is on my screen/display. Please see the attached image.

It isn't a big deal but is a little distracting and semi covers the TLHS of the menubar, the address bar and my bookmarks.

I am running Windows 10 64bit and Firefox is fully updated.

As my question title says.... I have just attached a 4K 3840X2160 TV as a monitor and this whitish overlay is on my screen/display. Please see the attached image. It isn't a big deal but is a little distracting and semi covers the TLHS of the menubar, the address bar and my bookmarks. I am running Windows 10 64bit and Firefox is fully updated.

Chosen solution

You may have installed a lightweight theme (Persona) that is broken.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
  • Do NOT click the "Refresh Firefox" button on the Safe Mode start window
Read this answer in context 👍 1

All Replies (5)

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 10 Contributor
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Hi louwin, unfortunately the screenshot didn't come through. Could you re-upload it? You can attach it to a reply:

https://support.mozilla.org/questions/1151620#question-reply

Louwin
Louwin Question owner
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Sorry the image didnt go through....

Trying again....

I think that should have it....

Still doesnt show in the preview but thumbnail shows!?

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Chosen Solution

You may have installed a lightweight theme (Persona) that is broken.

Start Firefox in Safe Mode to check if one of the extensions ("3-bar" menu button or Tools -> Add-ons -> Extensions) or if hardware acceleration is causing the problem.

  • Switch to the DEFAULT theme: "3-bar" menu button or Tools -> Add-ons -> Appearance
  • Do NOT click the "Refresh Firefox" button on the Safe Mode start window
Louwin
Louwin Question owner
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You're right, Thanks cor-el  :)

Virtually ALL my themes were the same except Default.

Have to find a theme I like that works.... Or maybe the theme authors will get it right now that they know!?

Thanks again  :D

James
James
  • Top 25 Contributor
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The Themes you likely have are just background images and not actual Complete Themes.