In the Reveal Formatting panel of the Control Board are listed the font colors. For "green" in English it looks like this:
In the German language "green" means "grün". Obviously because of the "Umlaut" (= "ü") in the word "grün", a strange letter (chinese or something like that?) appears instead of the correct ones:
The correct letters would be "ün" (or "uen" if the Umlaut cannot be generated).