Language change does not change the user interface language

I cannot get the language changed to german. I already tried setting the globalisation to de and de-DE. Your language files look good, but the user interface doesn't change after code generation. It is still "about" and "new blabla". I think this may be a problem with the generator that doesn't use the value?
I use the WebsiteFactory (no solution). Maybe you can help me.

Thanks in advance,
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