Package: x2goserver Version: 4.0.1.15 Severity: wishlist
Technically Openbox is just a window manager, not a desktop environment. However, it can be launched as an X11 session via the "openbox-session" command, so it should be very easy to add support for.
I intend to commit this to the release/4.0.1.x branch and then cherry-pick to master.