Hello Bernard,
hello Folks

I know the term too, being from Germany.
In the part where I grew up it also had a slang meaning like
"In my Skull I carry two pounds of dogpoop ...and it's a horrible smell, out of my mouth, nose and ears ...
But I think nobody will notice" .

It's a good thing Bob noticed, and told us ......

Have a good weekend,
stay away from Kloppers, wherever you may be

Cheers,
GROETJES,
Olaf