add "Run in background" to the System integration section
This should use the background table in the flatpak permission store - the flatpak portals now monitor applications that are running without open windows ("in the background"), and notify the user about that. This permission is used in deciding whether the app is allowed to run in the background or now, and having a switch in the application panel to change it would be very valuable. One reason is that I want the default action of the notification to open this settings panel, which only makes sense if the "run in background" permission is shown.
We can also consider adding a "Start at login" switch. The portal lets applications request that as well, and it works by creating an autostart file for the application, so that would be what the switch would control - whether the autostart file is there or not.