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problems opening firefox after updating windows 10 with (KB5035845) and 10.0.19041.4163

  • 3 replies
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  • Last reply by zeroknight

engnrman
engnrman
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Windows Updates (KB5035845) and 10.0.19041.4163

After these latest updates, EVERY, Firefox browser (derivatives included, i.e. LibreWolf, etc...) are opening VERY slowly. Its almost like the browser is freezing while opening for around 10 - 20 sec, then opening. It used to open within a second or two. If I uninstall the updates the problem goes away, BUT, windows re-installs them automatically. After it is up and running its ok. The problem seems to be on startup only.

Windows Updates (KB5035845) and 10.0.19041.4163 After these latest updates, EVERY, Firefox browser (derivatives included, i.e. LibreWolf, etc...) are opening VERY slowly. Its almost like the browser is freezing while opening for around 10 - 20 sec, then opening. It used to open within a second or two. If I uninstall the updates the problem goes away, BUT, windows re-installs them automatically. After it is up and running its ok. The problem seems to be on startup only.

All Replies (3)

zeroknight
zeroknight
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  • Click the "Clear startup cache" button in about:support.
  • Reset fonts to default in Windows Control Panel > Appearance and Personalization > Fonts > Font Settings > Restore default font settings.
  • Set MOZ_PROFILER_STARTUP=1 environment variable to capture a startup performance profile.
engnrman
engnrman Question owner
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none of that helped. After I deleted the cache it actually started even slower. It does start instantly when I check troubleshoot mode though. I have no extensions or themes that cause it. I disabled the default, which is all I had installed, and it still happens on restart.

Modified by engnrman

zeroknight
zeroknight
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The first start after clearing the startup cache is expected to be slower but subsequent starts should be faster.

engnrman said
It does start instantly when I check troubleshoot mode

Does it still happen if you disable hardware acceleration?

Try changing gfx.e10s.font-list.shared and gfx.font-list-omt.enabled to false in about:config.