What I expected to happen was...:
Was a superflat world with a layer dirt and the void biome.
What actually happened was...:
Everything went well into I tried to go into the void which in turn crashed my game
Steps to Reproduce:
1. Go to create new world
2. Chose the new void preset and change the layer of air to dirt
3. Last when the world is loaded break the dirt layer and go into the void
Dupe of MC-88357 if you had F3 on. Did you have F3 mode/debug mode on at the time?