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Why is Firefox Suddenly Taking Over my CPU?

  • 4 replies
  • 2 have this problem
  • 54 views
  • Last reply by jclarkw
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jclarkw
jclarkw

Today Firefox has suddenly started using ~20% of my CPU capacity, causing my cooling fan to run high most of the time. Since I had been running Firefox v.149.latest, I tried updating to v.150.0, but that made no difference.

It's not Firefox by itself (only Task Manager open) but whenever I open another tab with almost any website (including this one) that CPU usage spikes. What gives?!

Details: Running under Windows 10 Pro (yes, I have installed the ESU package, good until thi8s fall) on a Lenovo P1 Gen 2. Currently running Firefox inside a Sandboxie Pro v1.17.4 sandbox.

Please Help! -- jclarkw

Today Firefox has suddenly started using ~20% of my CPU capacity, causing my cooling fan to run high most of the time. Since I had been running Firefox v.149.latest, I tried updating to v.150.0, but that made no difference. It's not Firefox by itself (only Task Manager open) but whenever I open another tab with almost any website (including this one) that CPU usage spikes. What gives?! Details: Running under Windows 10 Pro (yes, I have installed the ESU package, good until thi8s fall) on a Lenovo P1 Gen 2. Currently running Firefox inside a Sandboxie Pro v1.17.4 sandbox. Please Help! -- jclarkw

All Replies (4)

jclarkw
jclarkw Question owner

I'm now running Firefox outside the sandbox, and almost everything I said above is still true except that this site no longer hogs CPI. Most others still do.

Since I'm now outside the sandbox, I can probably "Send Data," but that option seems not to show up in a reply...

--jclarkw

jclarkw
jclarkw Question owner

Is nobody else seeing this problem? Or are no solutions available? -- jclarkw

perrymwt
perrymwt

I'm having the same problem, but only when playing YouTube videos. Checking in task manager show one Firefox process showing very high usage. It does sometime goes down after a while.

jclarkw
jclarkw Question owner

For solution to this problem, see https://support.mozilla.org/en-US/questions/1578564#answer-1816178

Finding the offending add-on was not as easy as it seems. Perhaps time is required for some of these extensions to get triggered and cause trouble? -- jclarkw

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