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Firefox uses a lot of CPU

  • 5 replies
  • 2 have this problem
  • 85 views
  • Paskiausią atsakymą parašė philipp

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Firefox is my go-to browser on all my computers, but for some reason on my Win10 laptop it uses 30-60% CPU at all times, while my opera browser uses 1-5%. Both idle with same amount of tabs, or zero tabs. I've tried reinstalling multiple times, many versions, did the safe mode, did the refresh button.

Firefox is my go-to browser on all my computers, but for some reason on my Win10 laptop it uses 30-60% CPU at all times, while my opera browser uses 1-5%. Both idle with same amount of tabs, or zero tabs. I've tried reinstalling multiple times, many versions, did the safe mode, did the refresh button.

Chosen solution

hi, can you try if the following improves the performance problem: go to the firefox menu ≡ > options > privacy & security panel and under permissions check the setting to prevent accessibility services from accessing your browser.

Skaityti atsakymą kartu su kontekstu 👍 2

All Replies (5)

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Chosen Solution

hi, can you try if the following improves the performance problem: go to the firefox menu ≡ > options > privacy & security panel and under permissions check the setting to prevent accessibility services from accessing your browser.

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Hi, as running a beta anything can and will happen. Please go to Options --> Privacy & Security --> Permissions and put a check mark in the box to Prevent Accessibility Services .......

Then please back up to General on left side Menu then down to Performance and uncheck use Performance settings, then change the Content Processes down to 2 and try that after rebooting. Also go up higher, lower till find the sweet spot.

Yes see that you are in safe mode when posted this.

Note this % can increase or decrease for every version and any cpu. I have several and some run more than others with Firefox.

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philipp said

hi, can you try if the following improves the performance problem: go to the firefox menu ≡ > options > privacy & security panel and under permissions check the setting to prevent accessibility services from accessing your browser.

This actually seems to have solved the problem, at least during the past 24h of usage. I tried everything before... how come this one setting draws up so much CPU power ?

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Are there any downside risks to checking the box to "prevent..." (as described in earlier posts in this thread)? Any other considerations?

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unless you're vision impaired and depending on screenreaders, braille displays and other assistive technologies there are only upsides.