Preparing spawn area spams 0%

Affects 1.13-pre4, I get this error when tryed to create a new world in 1.13-pre4:

https://hastebin.com/qexohexuke.md

I now have this bug in 1.13-pre4.

Same here with 1.13-pre4. Tested on three different Win10 machines:
Error Description: "Writing into PalettedContainer from multiple threads".
Crashes on first creation of a world. On later loading of the same world it never passes 4% of preparing the spawn area, but without crashing.

Likewise. Same error.

However, the world always crashes. Though the Launcher does not show an alert like it usually does, unless the game's process is ended from Task Manager.

Intriguing that some of us didn't have this error with the previous snapshots like others did.

Can't load into any world. Loading always stops at 'Preparing spawn area'.

edit 1.13 pre4

@unknown, your's is a different issue: MC-132073

No longer Happens in 1.13.1-pre1.