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Thin white line persists at the bottom of the browser, seen on dark backgrounds and anything with colour

  • 5 replies
  • 2 have this problem
  • 2 views
  • Last reply by FredMcD

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Thin white line persists at the bottom of the browser, seen on dark backgrounds and anything with colour. Also persists in fullscreen videos and in browsing in general, when I switch out of firefox onto Windows Desktop, I notice the problem is firefox exclusive. the white line that persists is very thin above the taskbar. Hardware acceleration is disabled.

Thin white line persists at the bottom of the browser, seen on dark backgrounds and anything with colour. Also persists in fullscreen videos and in browsing in general, when I switch out of firefox onto Windows Desktop, I notice the problem is firefox exclusive. the white line that persists is very thin above the taskbar. Hardware acceleration is disabled.
Attached screenshots

Modified by SunnyM

Chosen solution

It could be the work of one of your add-ons. Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; <Control>(Mac=<Command>)<Shift> A)

In the Add-ons Manager, on the left, select Extensions. Disable a few add-ons, then Restart Firefox.

Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.

If the problem continues, disable some more (restarting FF). Continue until the problem is gone. After, you know what group is causing the issue. Re-enable the last group ONE AT A TIME (restarting FF) until the problem returns.

Once you think you found the problem, disable that and re-enable all the others, then restart again. Let us know who the suspect is, detective.

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All Replies (5)

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Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac=Options)
key, and then starting Firefox. A small dialog should appear. Click Start In Safe Mode (not Refresh).

Is the problem still there?

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no the issue is gone, but when I close and open firefox normally, the issue returns, what could be the problem? I have flash, 360 total security internet protection, adblock origin and firefox test pilot installed as addons. I noticed in safe mode the addons were disabled, could the problem be because of the addons?

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Chosen Solution

It could be the work of one of your add-ons. Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; <Control>(Mac=<Command>)<Shift> A)

In the Add-ons Manager, on the left, select Extensions. Disable a few add-ons, then Restart Firefox.

Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.

If the problem continues, disable some more (restarting FF). Continue until the problem is gone. After, you know what group is causing the issue. Re-enable the last group ONE AT A TIME (restarting FF) until the problem returns.

Once you think you found the problem, disable that and re-enable all the others, then restart again. Let us know who the suspect is, detective.

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After following your given method very closely, I've discovered this issue was due to an addon I had installed name 360 internet protection. 360 internet protection is the culprit in my eyes, my dear Watson! Thank you so much for your assistance

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That was very good work. Well done.

Contact its support site and talk to them about this.