OtakuMegane

Confirming this is occurring in 18w43b. Tried with the given preset as well as a modified ocean preset: minecraft:bedrock,252*minecraft:sand,3*minecraft:water;minecraft:deep_ocean;biome_1

Confirming this still occurs in the 1.13 release. I've been able to consistently trigger the bug by teleporting to coordinates at 10,000,000+ and moving around for a few minutes. Going to 12 million and higher it often crashes within seconds. Coordinates closer in sometimes also caused the crash but not as often. Attempting to enter the world again causes another crash. Tried this across several different worlds with random seeds, all newly created in 1.13.