The main reason I want to use firefox ESR is to use a proprietary database tool for work that only allows oracle-java based web logins for linux (or a windows only thin client). I also want to use the full version of the outlook web application which only works in firefox. I don't want to run the NPAPI plugins for normal web browsing and email.

I have the repo version of firefox installed and firefox ESR installed in /opt/firefox and linked to /usr/local/firefox-esr

When I run firefox any attempt to run firefox-esr either brings up a window without the NPAPI plugins.

If I try running with the --new-instance or --no-remote options I receive the following error:

Firefox is already running, but is not responding. To open a new window, you must first close the existing Firefox process, or restart your system.

Regardless which one I start first, I can only open that one, and get the above error if I attempt to sidestep.

What makes this an especially annoying problem is that I often have to respond to emails that I need to access the database to deal with. So either I close and open many windows.

  • What error did the Windows-only thin client give when you attempted to run it in Wine? Sep 6, 2017 at 23:52
  • You may also use the profile manager.
    – neverMind9
    Jan 20, 2018 at 10:51

1 Answer 1


You need to use -no-remote option, as in firefox -no-remote.

From man firefox:


Don't connect to any other running instances of firefox. Use this if you want to run firefox in an entirely new process. By default, firefox will delegate a command to an already running instance.

You'll also need separate profiles for Firefox and Firefox-esr, which can be created with with firefox -P Profile Manager.

  • I tried this, it's in my original post. Actually the firefox command line says --no-remote and the manual says -no-remote. I tried both
    – N8tron
    Apr 14, 2017 at 17:00
  • This is interesting, have you tried creating a different or duplicate profile for the second firefox process? It works as expected here. Apr 14, 2017 at 20:10
  • mikewhatever: that is interesting. What versions are you using? I'm in ubuntu 16.04. firefoxESR 52.0.2 (64bit) and firefox 52.0.02 (64bit).
    – N8tron
    Apr 14, 2017 at 20:37
  • Okay forget the versioning. Creating a new profile and manually loading them with the firefox -P works. If you want to put that in a solution I'll accept it.
    – N8tron
    Apr 14, 2017 at 20:42
  • -no-remote, --no-remote and --new-instance did not work for me, but running FF with -P did the trick! So I run firefox-esr -P, created a new profile for my esr and everything seem fine now.
    – Shautieh
    Apr 18, 2017 at 2:27

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