Dimension Biome Weight

Not applicable
Issue description

I want to add custom biome weight to my dimension, Setting the custom weight of a custom biome that generates in a custom dimension don't work, it works only for overworld

Like, i set a custom biome weight to 20, and one to 1

The biome weight in the dimension will be equal and not rarer

Issue comments

This is due to the way mutli-biome is handled. If this gets changed in 1.16.x, biome handling might improve.

Is there a way to fix it by adding many times the same biome?

Either adding it many times in the list or duplicating the biome of element and add them