Friseur
Berlin, Germany
Pascal Duez

That mark above the ‘u’ is not an umlaut (ü). As Florian Hardwig explains:

The bar or hook is a “courtesy mark” (as Ken Barber calls it) a courtesy to the reader to emphasize that this is a ‘u’ and not an ‘n’. I use the tag “u distinguisher”.

The u hook was a common means in German handwriting and was indispensable with the zigzag style of Kurrentschrift. It has survived in some more contemporary (script) lettering styles.

Related and confusing: the habit of putting a (straight) bar on the ‘n’, to denote a double ‘n’.