Bottom bar not hiding after switching window

[Simon Frei <freisim93@gmail.com>]

I more or less recently switched over from XFCE to KDE and must say, I
am pretty impressed :) 
Thanks a lot for packaging this fine DE for debian!

I am on debian testing.
One quite annoying behaviour I observe is that the bottom bar (set to
auto-hide) is not auto-hiding when switching windows. It does auto-hide
when I move the mouse onto the bottom bar and away again. That's quite
annoying especially on a small laptop screen when the open window has an
input field at the bottom (like most messengers).
Can anyone reproduce? I assume not, at least I couldn't find any info on
anyone having the same problem online.
Is there a cache/config file relevant to this behaviour I could check or
move out of place to see if it's a misconfig?

Thanks in advance for any help.

Cheers,
Simon