I would like to set an environment variable so that it is set when I launch a specific Flatpak application, and only set for this application. How do I go about doing this in a permanent manner?
You can do this via the
flatpak override command.
To set only one environment variable you can use this syntax:
flatpak override --env=VARIABLE_NAME=VARIABLE_VALUE full.application.Name
To set multiple environment variables you can use this syntax:
flatpak override --env="VARIABLE_NAME_ONE=VARIABLE_VALUE_ONE VARIABLE_NAME_TWO=VARIABLE_VALUE_TWO" full.application.Name
This will set it globally and therefore requires you to run the command as root. If you want to do this for your current user, you can add the
--user parameter to the command, like so:
flatpak override --user --env=VARIABLE_NAME=VARIABLE_VALUE full.application.Name
Source and further reading: http://docs.flatpak.org/en/latest/flatpak-command-reference.html#flatpak-override