This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Avatar for Username

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

This thread was archived. Please ask a new question if you need help.

Why does task manager show 6 "instances" of Firefox?

  • 4 replies
  • 1 has this problem
  • 1084 views
  • Last reply by Sue

Sue
Sue
more options

I started using Firefox on a Windows 10 laptop. I checked Task Manager as the computer is slow. It shows 6 instances of Firefox, all 6 using memory, with one of them showing CPU usage.

Is this "normal"? Is this how Firefox works? Thanks.

I started using Firefox on a Windows 10 laptop. I checked Task Manager as the computer is slow. It shows 6 instances of Firefox, all 6 using memory, with one of them showing CPU usage. Is this "normal"? Is this how Firefox works? Thanks.

Chosen solution

Yes, this is how it works. It's not "instances", but "processes".

Read this answer in context 👍 0

All Replies (4)

TyDraniu
TyDraniu
  • Top 10 Contributor
more options

Chosen Solution

Yes, this is how it works. It's not "instances", but "processes".

Sue
Sue Question owner
more options

Thanks.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
more options

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"
  • a process for the compositor thread
  • a process for the WebRender when this feature is enabled
  • a process for extensions

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

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

See also the about:memory page for information about the process IDs.

Sue
Sue Question owner
more options

I appreciate the explanation, thanks.