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CPU usage high even in safe mode

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  • Last reply by FredMcD

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Hello. My Firefox (latest stable version) is using a lot of CPU. I decided to see if it remained this way in safe mode, and it gets a bit better, but still very heavy, never going below 30%, even when nothing is being loaded, nor any plugin is activated. I love (hate, actually) to blame one of my addons, but with the issue happening in safe mode that's not an option. Any suggestions?

(Flash, Java, Adobe Reader are already cleared out as possible causes...)

EDIT: (1) disabling/enabling hardware acceleration also didn't produce any difference; (2) Adobe Acrobat, OpenH264 video codec, Adobe CDM Primetime, and Adobe Flash plugins are always active, all others are set to "Ask to activate", but then again CPU usage is high even in safe-mode with only java-pdf-flash-video-free tabs open.

Hello. My Firefox (latest stable version) is using a lot of CPU. I decided to see if it remained this way in safe mode, and it gets a bit better, but still very heavy, never going below 30%, even when nothing is being loaded, nor any plugin is activated. I love (hate, actually) to blame one of my addons, but with the issue happening in safe mode that's not an option. Any suggestions? (Flash, Java, Adobe Reader are already cleared out as possible causes...) EDIT: (1) disabling/enabling hardware acceleration also didn't produce any difference; (2) Adobe Acrobat, OpenH264 video codec, Adobe CDM Primetime, and Adobe Flash plugins are always active, all others are set to "Ask to activate", but then again CPU usage is high even in safe-mode with only java-pdf-flash-video-free tabs open.

Modified by cloudchasingfun

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Let's rule out the plugins anyway.

Type about:addons<enter> in the address bar to open the Add-ons Manager. Hot key; <Control>(Mac:<Command>) <Shift> A)

On the left side of the page, select Plugins. Set all of them to Ask.

At the top right is a link to check your plugins.


Start your Computer in safe mode with networking. Then start Firefox. Try Safe web sites. Is the problem still there?

Starting The Computer In Safe Mode;
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