After downloading the pre-release 9 I gone in my world using the data pack I'm making (it works in pre8) and after 30-60 the game crashes

The world was created in pre8

Creating a world in pre9 doesn't crash the game

Adding data packs in worlds created in 1.13-pre9 doesn't crash the game

Opening in 1.13-pre9 a 1.13-pre8 world doesn't crash the game

Adding data packs in 1.13-pre9 in worlds created in 1.13-pre8 doesn't crash the game

Loading a world like the bugged world at the start of the description doesn't crash the game...

so that world is bugged

I'll make a new one