The world types "Large Biomes", "AMPLIFIED" and "Single Biome" show up either as the "Custom" world type (in 1.20.6) or as the "Default" world type (in 1.21-rc1) when re-creating a world with that world type.

Steps to reproduce:

1. Create a world with the world type "Large Biomes", "AMPLIFIED" or "Single Biome".
2. Exit to the world list and with the created world selected, press the "Re-Create" button.

Observed result:
The world type is listed as either "Custom" in 1.20.6 or as "Default" in 1.21-rc1.

Expected result:
The world type is correctly listed as "Large Biomes"/"AMPLIFIED"/"Single Biome" depending on the world type of the original world.

Note:
The re-created world has the same world type as the original; this is purely a visual bug in the "Re-Create" menu.