Made Debug World mutable, meaning that you can now survive inside a Debug World.
As you can see in the image, the water also flows (since they're disappearing as if they were leaves on trees)
While it is possible to grow trees, it might be hard to come across one so get it while they're there!
This mod also made the Nether and The End mutable, which means that you can also take advantages of those two dimensions' resources!