Not at all uncommon. The dialect of Brussels has something similar: “schroumpf”. This word has become famous the world over, albeit in translation. You likely know it as “smurf”.
> The word “smurf” is the original Dutch translation of the French "schtroumpf", which, according to Peyo, is a word he invented during a meal with fellow cartoonist André Franquin when he could not remember the word salt.