It is definitely a thing with an umlaut. It makes a difference when you pronounce it wrongly and I always do. I was the joke of the company when I spoke German as I was always pronouncing the words wrong because I was never sure if there was an Umlaut there or not. As you can see here, the Umlaut which should be 2 little dots, is often written as something different – here a short line. Whether I say Buchse or Büchse is a joke amongst those German speaking and that is one of my biggest mistakes.