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Multiple Firefox.exe running at same time

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  • Last reply by cor-el

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when I check Task Manager I see I have multiple firefox.exe running at the same time.. Why?

when I check Task Manager I see I have multiple firefox.exe running at the same time.. Why?
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It is quite normal to see more Firefox processes running.

  • one process for the main Firefox thread (user interface)
  • one or more content processes, see:
    Options/Preferences -> General -> Performance
    remove checkmark: [ ] "Use recommended performance settings"
  • one process for the compositor thread
  • one process for the WebRender when this feature is enabled

Current releases may use additional processes for features like extensions. See also the sidebar on the about:memory page.

You can find the current multi-process state on the Troubleshooting Information page (about:support).

  • "Help -> Troubleshooting Information" -> "Application Basics":
    Multiprocess Windows
    Remote Processes

See also the Remote Processes section further down for more detail.