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In File Explorer sometimes there are 5 or 10 instances of Firefox all running at the same time. Is this normal?

I don't need to understand why so many instances of Firefox run in File Explorer. I'd just like to know if that is normal operation. Thanks!

I don't need to understand why so many instances of Firefox run in File Explorer. I'd just like to know if that is normal operation. Thanks!

Chosen solution

hi mike, yes what you're observing is normal - firefox is a multi-process application, which is running tabs and other tasks in separate processes for security, stability and performance reasons: https://wiki.mozilla.org/Electrolysis#Overview

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All Replies (4)

Chosen Solution

hi mike, yes what you're observing is normal - firefox is a multi-process application, which is running tabs and other tasks in separate processes for security, stability and performance reasons: https://wiki.mozilla.org/Electrolysis#Overview

Modified by philipp

Thanks Philipp!

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

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.