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20.0.1: File==>New Window & New Private Window will not open then Firefox will not stop running when application is closed

  • 2 replies
  • 1 has this problem
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  • Last reply by cmrkboh

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Although nothing appears to be happening when clicking on either New Window or New Private Window there seems to be processes started because when I try to close Firefox and reopen, I get an error message saying that Firefox is already running. My only option then is to stop the processes via Task Manager. I have tried (several times) to uninstall and reinstall.

Although nothing appears to be happening when clicking on either New Window or New Private Window there seems to be processes started because when I try to close Firefox and reopen, I get an error message saying that Firefox is already running. My only option then is to stop the processes via Task Manager. I have tried (several times) to uninstall and reinstall.

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 or otherwise make changes.

Create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

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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 or otherwise make changes.

Create a new profile as a test to check if your current profile is causing the problems.

See "Creating a profile":

If the new profile works then you can transfer some files from an existing profile to the new profile, but be careful not to copy corrupted files.

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Although advised not to, I finally hit the reset button in the Save Mode Window. This corrected the problem. I suspect a faulty add-on - I try and reject many. I will add them back on at a time as I develop the need. Thanks for you help.