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Firefox opening multiple processes

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  • Last reply by cor-el

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I have been wondering why Firefox is opening 8 processes when i start the program. I only have the starting page tab open. I also have tried reinstalling Firefox and changing the "use recommended performance settings" in the settings, which only slowed it down. Is this normal?

I have been wondering why Firefox is opening 8 processes when i start the program. I only have the starting page tab open. I also have tried reinstalling Firefox and changing the "use recommended performance settings" in the settings, which only slowed it down. Is this normal?
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Current releases have Fission enabled and in that case Firefox reserves some processes for future use (about:processes => Preallocated).

It is quite normal to see more Firefox processes running.

  • process for the main Firefox thread (user interface)
  • one or more content processes
    you see more content processes when Fission is enabled
  • process for the compositor thread
  • process for extensions
  • process for WebRender when this feature is enabled

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

  • "Help -> Troubleshooting Information"
    "Application Basics":<be>Multiprocess Windows and Fission Windows
    "Remote Processes" (Web Content)

See also the about:memory and about:processes pages for more information about all processes. There are several Boolean toolkit.aboutProcesses prefs on the about:config page to show more info on the about:processes page.