Seed: 1234

When you spawn, you will be next to a village that doesn't exist in 1.12.2. That village use the Savanna type, even if the biome is Ice Plains. Also, the different houses are above or slightly under the ground, there is no villager or zombies, there is no chest in the blacksmith's house and terrain can actually be generated in the house. Interestingly, one of the nearby village generated correctly, and it's the only one I found like that.

It's not the only structure who generated weirdly: the stronghold at -600, 1500 have a totally isolated library that is only partially generated (only a portion exists) and a fountain with a water source that doesn't update, even if we remove or add a block next to it.

No idea if it's linked, but that specific seed made the game crash a few times. (I didn't have any issue with the precedent world I generated).