As the story is told from various news sources.
An American was up and active at around 8:15AM on Saturday....in Dresden. This was in the Neustadt neighborhood of town....north of Elbe. This part of town is away from the tourist area. The guy, no name given.....41 years old.....was drunk (on the extreme side). Yeah, it's 8:15AM....so he's been drinking all night by my guess.
He does some talk here and there.....then throws up a Nazi salute....which gets him attacked by some German. No one says what provoked the deal beyond the Nazi salute. Cops come....arrest the guy.
Based on the normal fine business, if the story is proven absolute true.....it'll be near 500 Euro on the Nazi salute, and some type of fine (maybe 200 Euro) for public intoxication and bad behavior.
My typical advice to Americans and Brits.....enjoy the fine beer of Germany in the bier-garten type atmosphere, and avoid three particular topics:
1. Anything to do with WW II or Nazis.
2. Anything to do with Trump.
3. Anything that is harsh and critical of the magnificent Germans (sarcasm inserted into this column).
For the poor American? His trip will be cut short and he'll likely be asked to leave.