It has happened 4 times, I was playing in My own survival, then, from nothing, the Game freezed, I proceeded yo close the programa, but when I did that, it crashed. I was doing this: walking in the Nether very fast with soul speed, then I went back yo the normal dimension and a few minutes lager the Game crashed. In the second case I was exploring the overworld, I went very far from My spawnpont, from nothing, the game was frozen. In the other cases, I was going from one dimension to anonther a Lot of times (I was moving some items). I think that the issue comes from loading a Lot of chunks.