Restart plasma-desktop without logging out

It turns out this is quite easy and works fine:
Alt+F2

killall plasma-desktop

Alt+F2

plasma-desktop & 

And that's it. It will take couple of seconds but it loads ok. Also, killing krunner and restarting it from Konsole doesn't seems to be a problem. For those of you, which see something like 4GB for plasma-desktop and 2GB for krunner. 

By the way, this seems to be the problem also with "kdesu firefox" not working (it returns a stub).