[Bug] Colored Floodfill Lighting doesn't work on newer versions of Minecraft/Iris

[HarperMeows]

The first image is taken on Minecraft 1.20.6 using Iris 1.7.0. The second image is taken on Minecraft 1.21.4 using Iris 1.8.5. It works on Optifine using version 1.21.3, but Iris doesn't display it properly on newer versions of Minecraft.