Clouds are visible and don't render correctly when they are turned off

The bug

Even when clouds are turned off, they still are visible. They also do not move on the screen and stay at the same location even if you move the camera, and they show up in the Nether.

To reproduce

1. Turn on Clouds
2. Let any world load for at least a moment
3. Turn off clouds
   → Clouds are now permanently stuck in one position, even when leaving and entering a world.