Haha, of course :) Germans are nice people! It's just a joke, since Germany is mute-land in some Slavic languages heh
Do you know, why? Many foreigners have come to Russia while Petr The First was a tsar. There were Germans, Dutch, Swedes, Danish people, etc. The majority of Russians didn't speak their languages and called them 'mute' because 'they don't speak our language so they're mute'. Then this demonym was assigned to Germans, other nations was named according to names of their countries. :).
"Mute", because they didn't speak a Slavic language. There's a theory that Slavs/Slavic (I mean word for Slavic and Slavs in Slavic languages) means something like "speaking (lit. using words)", because long time ago there was one Proto Slavic language used by Slavs and a dozen of other they couldn't understand.
There's definitely nothing wrong with that. The beta still has very many gaps like this one. It would be helpful to always report when in doubt :)
When I was in Switzerland, there was some graffiti on the wall in the hostel that said, "Smile, or you might become Swiss." :-)