Matthew Garrett

Well, GNOME could easily support KDM's fast user switching interface. It has been there unchanged since years before GDM's current one. KDE Plasma does try hard to support GDM's current interfaces despite the continuous catchup games they have to play because GDM keeps changing its interfaces to desktops arbitrarily (because it only cares about GNOME). GNOME shows no interest whatsoever in doing the same for KDM. This sucks.

(FWIW, the only reason shutdown/restart works in GNOME even with KDM is because GNOME now uses ConsoleKit's interfaces to do so, which bypasses the display manager entirely. Of course, this means the policy settings set for KDM in System Settings will get ignored and PolicyKit policies will be used instead. Yet another case of different policies for the same thing. As for GDM, it just dropped its shutdown/restart interfaces, which also required KDE Plasma to play catchup with new incompatible interfaces.)