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Firefox is not even opened, but its process is slowing my computer

  • 2 replies
  • 1 has this problem
  • 4 views
  • Last reply by rouvenster

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Hello, I have no issue with the browser itself, very fast and smooth. I open it with no error message, close it, no problem. But several times while troubleshooting for something not related at all, I discover several processes firefox.exe (something like 5 or 6) running in the task manager while the browser itself is closed. Today was even more crazy, as I was playing GTA V, I noticed big lags with no apparent reasons. I checked the task manager, and discovered that Firefox.exe (browser not even opened) used 5 times more CPU resources than GTA V. Could it be some kind of a virus using a fake process name for mining or something similar ? Just seems too crazy to be the actual Firefox browser doing heavy work while being closed. Screenshot below CPU is Ryzen 5 5600X Thanks for the help

Hello, I have no issue with the browser itself, very fast and smooth. I open it with no error message, close it, no problem. But several times while troubleshooting for something not related at all, I discover several processes firefox.exe (something like 5 or 6) running in the task manager while the browser itself is closed. Today was even more crazy, as I was playing GTA V, I noticed big lags with no apparent reasons. I checked the task manager, and discovered that Firefox.exe (browser not even opened) used 5 times more CPU resources than GTA V. Could it be some kind of a virus using a fake process name for mining or something similar ? Just seems too crazy to be the actual Firefox browser doing heavy work while being closed. Screenshot below CPU is Ryzen 5 5600X Thanks for the help
Attached screenshots

Chosen solution

I tried every options recommended to me, it didn't help. So I uninstalled Firefox, wiped stuff and cleaned the registry using Ccleaner, and reinstalled it using chocolatey. Now, when I click the "X" on the top right side, i can see on the task manager the processes closing immediately. I guess it is solved now, just a shame I didn't know what caused it. Hope it won't come back

    • EDIT**

It came Back. Permanently removed Firefox and using Edge instead with the exact same settings and extensions. In Edge settings, there is a switch to turn off saying "Let processes and extensions run even when Edge is closed". I wish there was the same thing in Firefox.

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All Replies (2)

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Hey there!

Please see te following link on how you can reduce the amount of CPU resources Firefox takes:

https://support.mozilla.org/en-US/kb/firefox-uses-too-much-memory-or-cpu-resources

Hope I helped!

Kind regards,

Bithiah

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Chosen Solution

I tried every options recommended to me, it didn't help. So I uninstalled Firefox, wiped stuff and cleaned the registry using Ccleaner, and reinstalled it using chocolatey. Now, when I click the "X" on the top right side, i can see on the task manager the processes closing immediately. I guess it is solved now, just a shame I didn't know what caused it. Hope it won't come back

    • EDIT**

It came Back. Permanently removed Firefox and using Edge instead with the exact same settings and extensions. In Edge settings, there is a switch to turn off saying "Let processes and extensions run even when Edge is closed". I wish there was the same thing in Firefox.

Modified by rouvenster