Maybe he is swiss, they have some weird quirks. Like they don’t do the ß either I believe. Maybe they don’t use Umlaute. I’d ask them, but I can’t understand them when they talk. That is not even a joke.
There are more differences but they are in the vocabulary. The Swiss use a lot of French words. Velo instead of Fahrrad, Trottoir instead of Bürgersteig, Cheminée instead of Kamin, Porte-Monnaie instead of Brieftasche, Camion instead of Lastkraftwagen, and so on.
Maybe he is swiss, they have some weird quirks. Like they don’t do the ß either I believe. Maybe they don’t use Umlaute. I’d ask them, but I can’t understand them when they talk. That is not even a joke.
The only orthographic difference is not using ß.
There are more differences but they are in the vocabulary. The Swiss use a lot of French words. Velo instead of Fahrrad, Trottoir instead of Bürgersteig, Cheminée instead of Kamin, Porte-Monnaie instead of Brieftasche, Camion instead of Lastkraftwagen, and so on.
They also differ by region a lot. In Zurich you’ll see fewer french words and more anglicisms.