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Multiple instances of Firefox

  • 3 replies
  • 1 has this problem
  • 6 views
  • Last reply by cor-el

mkqgl0
mkqgl0
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I have used Firefox for years with a short diversion to Chrome for a few months. Despite regular restarts the browser is slow. Today I have 4 tabs open but task manager shows 10 (and sometimes 20) instances of Firefox running. Can anyone help me figure out what is going on? Thanks in advance

I have used Firefox for years with a short diversion to Chrome for a few months. Despite regular restarts the browser is slow. Today I have 4 tabs open but task manager shows 10 (and sometimes 20) instances of Firefox running. Can anyone help me figure out what is going on? Thanks in advance

All Replies (3)

FredMcD
FredMcD
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More than one process is normal for the current Firefox. http://www.ghacks.net/2016/07/22/multi-process-firefox/

Multi-process Firefox is codenamed "e10s". https://wiki.mozilla.org/Firefox/multiprocess

Start Firefox in Safe Mode {web link}

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

mkqgl0
mkqgl0 Question owner
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Fred, I started in safe mode. Currently have 6 tabs open and Task manager shows 8. What should my next step be? Thank you

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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You can check the Firefox Task Manager (about:performance) and about:memory pages.

It is quite normal to see more Firefox processes running.

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

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.