Comment # 25 on bug 954139 from Wolfgang Bauer

(In reply to Marcus Meissner from comment #24)
> thats why i still have sddm or systemd in my eyes for cause of this problem

The problem occurs on 13.2 with kdm too.
See bug#950864 (doesn't mention kdm, but I can reproduce it with kdm here).

So it's unlikely that sddm is causing this...