Water seems to be invisible when randomly generated under blocks. Underwater and most of the time it is fine. I have tried reloading my screens, but it stays invisible. This is in a snapshot, so who knows if this is it just not being ready yet. I have recently played on some historical versions (Like the first-ever versions) but I don't think that would play a role on this due to the fact that this world was created after that. It is a very small thing, but it does kinda bother me, heh.