October, 2018: "In Europe, Speech Is an Alienable Right: [the European Court of Human Rights] upheld an Austrian woman’s conviction for disparaging the Prophet Muhammad."

https://www.theatlantic.com/ideas/archive/2018/10/its-not-fr...

Without the need to agree or disagree with the ruling itself (which I cannot read about, as the article is behind a paywall, and I expect that the ruling is more nuanced than what the clickbait title suggests), the fact that a person was condemned for saying something for some reason (provocation to hate I would assume) does not mean that a mastodon server would be liable for relaying the information. Actually, politicians get condemned on a regular basis for diffamation or hate speech, but I never heard of any TV channel or newspaper being sued for having reported on the discourse of said politicians.

I have to say that I expected a bit more, as you mentioned "most content on the internet".

In Germany you are not allowed to downplay, deny or condone the Holocaust. It is part of the criminal code.

§ 130 iii StGB

https://www.gesetze-im-internet.de/stgb/__130.html

> Mit Freiheitsstrafe bis zu fünf Jahren oder mit Geldstrafe wird bestraft, wer eine unter der Herrschaft des Nationalsozialismus begangene Handlung [...] öffentlich oder in einer Versammlung billigt, leugnet oder verharmlost.

Extreme hate speech. In Germany, Nazi symbols and holocaust denial are illegal. I think Musk's new right-wing Twitter policies are going to run into that problem: https://www.theguardian.com/technology/2023/jul/10/twitter-f...

Nazi propaganda and holocaust denial would be the main ones; many European countries ban that. This is generally fairly narrowly defined, though.