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Mac high cpu usage

  • 2 replies
  • 8 have this problem
  • 31 views
  • Last reply by ae6dx

ae6dx
ae6dx
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I'm noticing very high CPU usage from Firefox as reported by OS X Activity Monitor. I have tried what is said here https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix?esab=a&as=aaq with no luck.

Is there some log file or something I can provide that will help figure out the high CPU?

I'm noticing very high CPU usage from Firefox as reported by OS X Activity Monitor. I have tried what is said here https://support.mozilla.org/en-US/kb/firefox-uses-too-many-cpu-resources-how-fix?esab=a&as=aaq with no luck. Is there some log file or something I can provide that will help figure out the high CPU?

All Replies (2)

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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Such issues can be caused by one or more of the installed extensions.

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

See also the about:memory page. you can open about: pages via the location/address bar like you open web pages.

ae6dx
ae6dx Question owner
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I have already checked extensions. What exactly do you need from the about:memory page?