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FireFox taking lots of CPU and moderate lag (not just typing)

  • 7 ŋuɖoɖowo
  • 0 masɔmasɔ sia le wosi
  • 9 views
  • Nuɖoɖo mlɔetɔ jonzn4SUSE

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I have tried fixing the config settings, I have tried uninstalling and reinstalling. I don't have any applications anymore (not even a background), and I have deleted and got rid of cache, history, etc.

But it still keeps lagging for me to the point that its hard to even use it now. I checked the task manager and even with just 1 new tab open, it was using 80% CPU. I changed the settings on it for the hardware like other replies said to do, and it still won't stop lagging.

It works perfectly in troubleshoot mode, but as soon as its gone, even when all the extensions and add-ons are removed, there's still a ton of lag. My computer is an Acer Nitro 5, I literally got it last year. Firefox was working up until 2 days ago just fine!

I can't seem to figure out the cause of it

I have tried fixing the config settings, I have tried uninstalling and reinstalling. I don't have any applications anymore (not even a background), and I have deleted and got rid of cache, history, etc. But it still keeps lagging for me to the point that its hard to even use it now. I checked the task manager and even with just 1 new tab open, it was using 80% CPU. I changed the settings on it for the hardware like other replies said to do, and it still won't stop lagging. It works perfectly in troubleshoot mode, but as soon as its gone, even when all the extensions and add-ons are removed, there's still a ton of lag. My computer is an Acer Nitro 5, I literally got it last year. Firefox was working up until 2 days ago just fine! I can't seem to figure out the cause of it

All Replies (7)

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see if your drivers are up to date or maybe your driver might be uninstalled

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AzZA said

see if your drivers are up to date or maybe your driver might be uninstalled

I checked the drivers now, it did lower the CPU usage (now it hovers around 70, but I've seen it as low as 55), but the lag is still there. I checked manually too whether there are drivers that need installed, nothing.

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Terry said

This link may help. https://support.mozilla.org/en-US/kb/diagnose-firefox-issues-using-troubleshoot-mode#w_the-problem-does-not-happen-in-troubleshoot-mode

I used the guide, but it didn't work. I don't have anymore extensions or add-ons, I tried refreshing firefox. Everything is up to date. So I'm very confused

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What security software are you running?

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jonzn4SUSE said

What security software are you running?

Windows Defender.

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If you have Windows Pro, try this option. https://www.howtogeek.com/399290/how-to-use-windows-10s-new-sandbox-to-safely-test-apps/ If not, download a vm app of your choice and see what happens. Also suggest getting a better understanding of what's running when your computer boots up. Use these tool to see if something is running that shouldn't be.

https://learn.microsoft.com/en-us/sysinternals/downloads/process-explorer https://learn.microsoft.com/en-us/sysinternals/downloads/autoruns

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