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Why is Firefox using 97%?

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Often my Firefox browser slows to a standstill. Using task manager, I see that CPU is often in the 80's and 90's %. What is causing this?

All Replies (7)

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Good evening,

it depends on how much you open your bookmarks and browser as busy. Furthermore, it is ook the age of the computer. Thank you for understand.

Best regards, David-Walczysko Volunteer supporter

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Firefox runs much better in safe mode. I notice it still occasionally uses 95% CPU, but usually for only a moment. Thanks.

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It could be the work of one of your add-ons. Type about:addons<enter> in the address bar to open your Add-ons Manager. Hot key; <Control>(Mac=<Command>)<Shift> A)

In the Add-ons Manager, on the left, select Extensions. Disable a few add-ons, then Restart Firefox.

Some added toolbar and anti-virus add-ons are known to cause Firefox issues. Disable All of them.

If the problem continues, disable some more (restarting FF). Continue until the problem is gone. After, you know what group is causing the issue. Re-enable the last group ONE AT A TIME (restarting FF) until the problem returns.

Once you think you found the problem, disable that and re-enable all the others, then restart again. Let us know who the suspect is detective.

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The CPU on my high-end i7 exceeds 55% constantly. We cannot uninstall the add-ons, because then it is unusable - because you guys completely destroyed the UI in later versions and forced those changes on us - remember?

Can we have FF V 3.5 with recent security patches and support for html5? That's all. Keep all the other bells, whistles and 'phone-app' / 'opera' looking stuff. Call it "Firefox Light Classic" or something.

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JKff22 Please go to the top of any support.mozilla.org web page and use the Ask A Question link; https://support.mozilla.org/en-US/questions/new This will let us look at your system details. No Personal Information Is Collected.

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JKff22 said

... Can we have FF V 3.5 with recent security patches and support for html5? That's all. Keep all the other bells, whistles and 'phone-app' / 'opera' looking stuff. Call it "Firefox Light Classic" or something.

You're joking, right?

Check out PaleMoon if you want a "retro" browser.