Follow-up from "mutter: Disable session management with mutter and gnome-kiosk"

The following discussion from !15 (closed) should be addressed:

• @jadahl started a discussion: (+1 comment)

  --sm-disable will not be there when built without X11 support, and isn't related to org.gnome.SessionManager so I doubt it will have an effect. I wonder if --no-x11 will be there in that case. @bilelmoussaoui?