Well, in theory you can also go to jail, for saying you think the catholic church is a organisation of criminal pedophiles. (blasphemie paragraph)
Does not happen in reality, though.
There are Nazis in jail though for denying the holocaust (Horst Mahler) and for trying to incite violence (Landser). Not for expressing their nazi ideology, but for direct calls for murder.
Plenty of NDP functionaries (and some AfD too) were fined or are on parole for Volksverhetzung. Just because it doesn't usually escalate into jail time doesn't mean the law is not being applied.[1]
Does not happen in reality, though.
There are Nazis in jail though for denying the holocaust (Horst Mahler) and for trying to incite violence (Landser). Not for expressing their nazi ideology, but for direct calls for murder.