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firefox.exe* uses large amount of cpu 40-50%

  • 1 reply
  • 1 has this problem
  • 12 views
  • Last reply by cor-el

tomcat867
tomcat867
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My computer slows and task manager shows firefox.exe* very large cpu usage.

My computer slows and task manager shows firefox.exe* very large cpu usage.

Chosen solution

You can try to disable OMTC and leave hardware acceleration in Firefox enabled.

  • about:config page: layers.offmainthreadcomposition.enabled = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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

You can check if there is an update for your graphics display driver and check for hardware acceleration related issues.

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All Replies (1)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

Chosen Solution

You can try to disable OMTC and leave hardware acceleration in Firefox enabled.

  • about:config page: layers.offmainthreadcomposition.enabled = false

You can open the about:config page via the location/address bar. You can accept the warning and click "I'll be careful" to continue.

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

You can check if there is an update for your graphics display driver and check for hardware acceleration related issues.