It's not uncommon, unfortunately (although the penalties are usually not so extreme). Usually it also happens to be the countries that have some large-scale territorial disputes with neighbors.

For example, in Russia, there's a law against "public calls to actions that would violate the territorial sovereignty". In practice, this means that saying something like "Crimea was illegally occupied" is technically illegal, and occasionally enforced.

I recall India mulled a similar law with Jammu and Kashmir in mind, although I don't think they ended up passing that.

It’s an interesting contrast with, say, sovereign citizens in the US. Law enforcement basically doesn’t care what they think about their sovereignty, they just treat them like any other person.