Choosing a biome in customized chooses the next biome on the slider

How to reproduce:
1. Create a customized world with a different biome, I chose "Roofed Forest"
2. Generate the world.
3. The world comes out as the next biome on the slider, Which for me was "Cold Taiga"

Edit: I tried to reproduce with the birch forest, It worked as intended, Bug might be rare.