Spawning weird after dropping sand into an end gateaway

This will never happen by normal playing, but a bug is a bug.

How to reproduce:

1. Enter the end
2. Kill the enderdragon
3. Enter the end gateway
4. search for another gateway
5. drop in a falling sand
6. enter it
7. sometimes you spawn normal, sometimes you spawn and suffocate, and in rare cases you spawn in the Void

here are videos