Minecraft 21w41a
This snapshot officially changes the random number generator used for worldgen. See the changelog.
New Random Number Generator
As mentioned in the previous snapshot post, the new generator is a random number generator based on the Xoroshiro128++ algorithm. It is not cryptographically secure, but it is significantly less exploitable than the default Java random number generator. This could mean that exploits such as the “swamp clay trick” or the “lapis trick” will become much harder to find.
Minecraft now has 2^64 seeds instead of 2^48, since Mojang fixed MC-236650.