Put the summary of the bug you're having here
What I expected to happen was...:
The world would open regularly.
What actually happened was...:
The game crashed.
MC-133739
The game crashes when opening a world from 1.13 pre-8
Resolved
Awaiting Response
0
Do you have the crash report from .minecraft/crash-reports? This might be the same issue as MC-133653 (which many people were getting)