Created attachment 466802 [details] screen shot ass seen in the attached screen shot
Can't say I've seen that, but I guess this is the same as described in https://bugs.kde.org/show_bug.cgi?id=376918
Is that issue gone with 5.5.0 or did you have a chance to visit your shortcut settings wrt the comment in related KDE bug?
(In reply to Andreas Sturmlechner from comment #2) yes, done in 5.5.0
Thanks, 5.5.0 is being stabilised right now.