German umlauts are transferred to the next character

[whitemilan]

When selecting an entry with a german umlaut (ä, ö or ü), the umlaut is transferred to the next character on ouput.

[nwormek]

I think this has something to do with unicode normalization. If I disable it with --ascii-input=true, it works as expected.

Edit: Almost. It outputs the result, but doesn't filter correctly anymore.