Minecraft Version: 1.21
Shader Loader: Iris v1.7.3
Shader Version: 2.2
This report that was printed into in-game chat:
terrain_solid.fsh: terrain_solid.fsh: 0(300) : error C1503: undefined variable "shadowtex1"

Examples of clouds

Turning off the "Colored Shadows" setting in the config

I have turned off and on the clouds and them turning green was fixed.
The problem with "Colored Shadows" still occurs.

I forgot to take a screenshot of the clouds during daytime, here's an example.

fixed