I just now realized this and I am not sure if this happens to everyone, but I realized that the little mob inside of a monster spawner, is gone. The little mob in the monster spawner completely vanished after I updated Minecraft to hotfix 1.13.1.

Please help! I left some images in the bottom to explain further detail.

Also, a crash has a chance of happening whenever I open my: inventory, settings, pause menu, character creator, and other HUD's except the ones in-game, such as crafting tables, furnaces, grindstones, etc.