GNOME 3.20 to Have Separate X11 and Wayland Sessions in Display Manager

To our surprise, we’ve discovered that the GNOME devs managed to implement quite a few things in GDM 3.19.2, such as the implementation of separate X11 and Wayland sessions, support for hiding the Wayland session if the login screen is powered by X11, as well as the removal of the “custom” session.