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Why are there more than one instance of Firefox running.

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  • Last reply by cor-el

RMN-Quest
RMN-Quest
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When I check for programs running in Task Manager, there are 4 or more instances of Firefox running. Why.? This never used to be the case, but ever since Firefox forced me to update to it's latest browser, I see more than one instance. Is this a bug in Firefox, or some other type of hack going on.

When I check for programs running in Task Manager, there are 4 or more instances of Firefox running. Why.? This never used to be the case, but ever since Firefox forced me to update to it's latest browser, I see more than one instance. Is this a bug in Firefox, or some other type of hack going on.

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cor-el
cor-el
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  • Top 10 Contributor
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It is quite normal to see three or more Firefox processes running.

  • one process for the main Firefox thread (user interface)
  • one or more content processes set via
    Options/Preferences -> General -> Performance
    remove checkmark: [ ] "Use recommended performance settings"
  • one process for the compositor thread (Windows;graphics)

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

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