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Background Files running

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  • Last reply by cor-el

svillecb
svillecb
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After just turning on my computer running Windows 10, I opened Firefox. I open 1 web site and noticed my computer showed a (16) prefix when loading Firefox. I opened the Task Manager and it showed that there were 15 instances of "firefox" running in the background. All showed a UAC Virtulization of "Disabled". But they also showed using 638.8MB of memory. I do not know whether these are necessary files that must run in the background or if the number of files indicates that my system has been hacked and someone else is in my system from outside. Any suggestions as to validity of these files running or how I might confirm that they should be running. I have noticed the number of excessive background files before but the number is never consistent which makes me fear I may have been hacked.

After just turning on my computer running Windows 10, I opened Firefox. I open 1 web site and noticed my computer showed a (16) prefix when loading Firefox. I opened the Task Manager and it showed that there were 15 instances of "firefox" running in the background. All showed a UAC Virtulization of "Disabled". But they also showed using 638.8MB of memory. I do not know whether these are necessary files that must run in the background or if the number of files indicates that my system has been hacked and someone else is in my system from outside. Any suggestions as to validity of these files running or how I might confirm that they should be running. I have noticed the number of excessive background files before but the number is never consistent which makes me fear I may have been hacked.

All Replies (1)

cor-el
cor-el
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  • Top 10 Contributor
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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":
    Multiprocess Windows and Fission Windows
    "Remote Processes" (Web Content)

You can possibly modify this pref in about:config set the number of content processes to 1.

You can check the about:memory and about:processes pages for info about all processes. There are several toolkit.aboutProcesses prefs in about:config to show more info. See also the about:unloads page for info about the tabs.