There’s been a singer that did it during a concert. Multiple times, too. She got a fine of 80.000€.

Another one is this case. He got a fine of 600€ for showing the salute with the left arm. Reasoning of the person that did it:“I thought it wouldn’t be forbidden with the left, I wanted to be provocative towards leftist protestors”.

I found another one where an artist who did it in public was fined 30 “Tagessätze” (your daily income) worth 50€ each, so 1500€.

So most punishment comes in the form of fines, imprisonment is rare. One must consider that usage of the Hitler Salute is covered under § 86a of our Penal Code (“Usage of Signs of anticonstitutional and terrorist organisations”), which is more tame than the § 130 of the same code, “Volksverhetzung”. That one would always be met with imprisonment (three months to five years), assuming you’re the instigator. But the bar is also a lot higher, since it requires you to actively sow hatred, instigate violence against certain people, be it based on sex, heritage, politics, birthplace, religion or whatever.

§ 86a StGB in English

§ 130 StGB in English