In order to run several Signal desktop instances in parallel, you can pass a –user-data-dir=<path> commandline option to signal-desktop.

When Signal Desktop is installed via flatpak, do the following:

1. Copy /var/lib/flatpak/app/org.signal.Signal/current/active/files/share/applications/org.signal.Signal.desktop to ~/.local/share/applications/Signal2.desktop
2. Then edit ~/.local/share/applications/Signal2.desktop and change lines 2-3 as follows (replace <user> with your username):

   Name=Signal 2
   Exec=flatpak run org.signal.Signal --user-data-dir=/home/<user>/.var/app/org.signal.Signal/config/Signal2 %U

Afterwards, you should find the second instance of Signal Desktop as „Signal 2“ in your application launcher.

When Signal Desktop is installed via snap, do the following:

1. Copy /var/lib/snapd/desktop/applications/signal-desktop_signal-desktop.desktop to ~/.local/share/applications/Signal2.desktop
2. Then edit ~/.local/share/applications/Signal2.desktop and change lines 2-3 as follows (replace <user> with your username):

   Name=Signal 2
   Exec=Exec=env BAMF_DESKTOP_FILE_HINT=/var/lib/snapd/desktop/applications/signal-desktop_signal-desktop.desktop /snap/bin/signal-desktop --no-sandbox --user-data-dir=/home/<user>/snap/signal-desktop/current/.config/Signal2 %U

Afterwards, you should find the second instance of Signal Desktop as „Signal 2“ in your application launcher.