So I was just messing around in the new snapshot. And then I got the idea to create and activate an end portal in the nether within a new world. When I entered this portal (which, to my surprise, was activated) I was send to the end. However, the spawning platform within the end was located in the air and near to where the exit portal is... This was clearly not supposed to happen, since I have never seen it before.

Me, being exited, made a screenshot of it and went on to see if it was only something that happened then, or if it was the world seed. But then I realized that I wasn't able to place blocks or use items anymore. And when a block was broken. It would reappear when a block was placed on that coordinate. Commands were still working.

When I tried to kill myself using the /kill command. I respawned. However, my character wasn't able to move, and I was inside my own character. Using the /tp command I was able to move myself around the world. Only my character stayed in the same location, not moving at all.

Each time I moved myself back to the nether portal, I entered the nether. But died as soon as I did. And when I relogged. I also died on the location my character was and wasn't able to respawn, since I didn't get the option to, nor did I get the death screen.