mjhjmtu

If you have gnome-terminal running, and want a new instance of the program, you might think that running gnome-terminal & from a shell would do the trick.

Astonishingly, this new instance behaves like some insipid Windows or Mac program; it only sends a message to the existing, running gnome-terminal to create a new window. If this one gnome-terminal process crashes, you lose all of the terminal windows!

(Of course, each window has its own shell, which is an independent process, but the actual terminal emulator and its GUI are managed from a single instance of the application.)

How can we create independent instances of gnome-terminal, each running in their own process, so that killing that process only destroys the window(s) associated with that process?

According to man gnome-terminal, the option you're looking for appears to be the confusingly-named

 --disable-factory
 Do not register with the activation name server, do 
 not re-use an active terminal.

However, the option is apparently removed in more recent releases so should not be relied on.

Due to the new client/server architecture (details here) you'll have to start separate instances of gnome-terminal-server. To do that you could use the --app-id switch:

/usr/lib/gnome-terminal/gnome-terminal-server --app-id my.first.Terminal

then use the client (with the same app-id) to create terminals¹ inside the new server :

gnome-terminal --app-id my.first.Terminal
gnome-terminal --full-screen --app-id my.first.Terminal
......

Another instance:

/usr/lib/gnome-terminal/gnome-terminal-server --app-id my.second.Terminal

and terminals:

gnome-terminal --geometry 80x24+200+200 --app-id my.second.Terminal
gnome-terminal --app-id my.second.Terminal
.....

Path to gnome-terminal-server might be different on your system.

^{1: Note that "you have 10 seconds to use the client to create a terminal inside the new server".}

I have been struggling with mc being in same alt-tab group as other terminal windows and found this solution.

https://chrisirwin.ca/posts/multiple-instances-of-gnome-terminal/

The guy (Chris Irwin) solves it for his mail routine. I did the same for mc with full success apart from mc icon within alt-tab but that is fine.

You'll need 3 files:

/usr/share/dbus-1/services/org.gnome.Terminal-mc.service

[D-BUS Service]
Name=org.gnome.Terminal-mc
SystemdService=gnome-terminal-server-mc.service
Exec=/usr/lib/gnome-terminal-server --class=org.gnome.Terminal-mc --app-id org.gnome.Terminal-mc

/usr/lib/systemd/user/gnome-terminal-server-mc.service

[Unit]
Description=GNOME mc Terminal Server
[Service]
KillMode=process
Type=dbus
BusName=org.gnome.Terminal-mc
ExecStart=/usr/lib/gnome-terminal-server --class=org.gnome.Terminal-mc --app-id org.gnome.Terminal-mc

/usr/local/share/applications/mc.desktop

This is your desktop entry for midnight commander. Either edit it directly in /usr/share/applications/... or move it from there to /usr/local/share/applications/mc.desktop to stress out that it is your own modified copy.
In any case, Exec entry should be modified to have gnome-terminal --app-id org.gnome.Terminal-mc -e mc

Exec=gnome-terminal --app-id org.gnome.Terminal-mc --hide-menubar --geometry=102x35 -e mc

Archive with all the above

https://we.tl/t-6rH5jduMG7
This is .tar.gz to unpack in your /. It will create files from above, plus .svg icon for mc.