Plasma 5.4 "File Manager - Super User Mode" not working

I suspect my problem is actually not related to OpenSUSE 13.2 but to the Plasma 5.4 desktop I’m using, but I wanted to post here, just in case.
KRunner is offering a handy “File Manager - Super User Mode” command, that starts dolphin with root privileges. In the past this used to work, but since Plasma 5.4 nothing happens after the password prompt.
Is there a way to get more information on why dolphin is not starting after the password prompt? Is this more likely a OpenSUSE issue or a Plasma issue?

Yep, I have the same issue here too (TW with KF5 Factory). You can also just run “kdesu dolphin” and it will work.

That’s good to know. Thanks!

Better use “kdesu dbus-launch dolphin”, otherwise there might be hangs when trying to open a file (at least there have been bug reports about this in the past, so the openSUSE specific “File Manager - Super User Mode” entry has been modified accordingly).

The menu entry does work fine here on 13.2 though, in both KDE4 and Plasma 5.4 (my own packages branched from KF5).

So using kdesu does work? That’s basically what KDE uses to run dolphin as root.
Maybe running “xauth -b” (as user, and then entering ‘q’ to quit) would help?
Sometimes there can be stale locks on .Xauthority that can prevent running applications as root in the user session.