Playskool here on the official server. Encountered an issue after I had killed the end dragon and begun mapping, I attempted to enter the end portal again and my client crashed. Upon reloading, I was several thousand blocks out above the void in the end. I repeated the process and the bug reproduced.

https://i.imgur.com/y6bKwAR.png screenshot of coords I ended up at

Happy to help debug this one as it seems to be persistent.

I've diagnosed why this bug seems to happen, I had used a scroll to return from a map which seems to have triggered the bug. After entering a map and leaving via the portal, the bug stopped ocurring.