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My firefox is using all of my CPU while doing nothing, I can even close firefox and it still uses 80% of my CPU. It uses all my CPU, can you help?

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  • Last reply by PavelkoT

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So I tried a few of the solutions with the problem and nothing seems to work. I Restarted firefox in safemode and it still uses 50% of my CPU and almost 100% with extensions

So I tried a few of the solutions with the problem and nothing seems to work. I Restarted firefox in safemode and it still uses 50% of my CPU and almost 100% with extensions

Chosen solution

Hi, that's not good. fyi : Extensions use aprox 20megs each give or take. Let's try this before disable anything : please uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 59.0.2 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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All Replies (5)

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Hi, Please : go to the Firefox 3 Bar Menu --> Options --> Privacy & Security panel and under Permissions check (put a tick in the box) the setting to Prevent Accessibility Services from accessing your browser.

Go to the 3 Bar Menu then Options --> General --> Performance and untick everything. change the recommended size lower then see how it runs. Note: 1 = No Multiprocessor = slow again. Try 2 Restart Firefox after making these changes please. Note : Hardware Acceleration is for Video Card, Monitor to see if remain off or to turn back on.

Also please run a scan : https://www.malwarebytes.com/

Please let us know if this solved your issue or if need further assistance.

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No none of these things worked

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Chosen Solution

Hi, that's not good. fyi : Extensions use aprox 20megs each give or take. Let's try this before disable anything : please uninstall Firefox. Then Delete the Mozilla Firefox Folders in C:\Program Files , C:\Program Files(x86) & C:\ProgramData Then restart system. Then run Windows Disk Cleanup. (Note: This should be Pinned and run Weekly, If never done below expect 10's of gig's) Then run it again and click the button that says Cleanup System Files. Note: your Firefox Profile is saved. But you should make a back up before you do :

Reinstall with Current Release Firefox 59.0.2 with a Full Version Installer

Please let us know if this solved your issue or if need further assistance.

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Ok that one worked thank you

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MisterSkids said

So I tried a few of the solutions with the problem and nothing seems to work. I Restarted firefox in safemode and it still uses 50% of my CPU and almost 100% with extensions

Please, read my message about the same problem: https://support.mozilla.org/ru/questions/1217832#answer-1114117