In Germany, there are two competing flight comparison engines with very similar names: fluege.de and flüge.de. How would you send an email to the customer supp

In Germany, there are two competing flight comparison engines with very similar names: fluege.de and flüge.de. How would you send an email to the customer support of flüge.de? How would you parse that domain? IDN is here, and it's here to stay.