Slab/stair shadows break with vibrant visuals

With vibrant visuals, sky light continues to pass through stairs/slabs (for example, stair roofs), illuminating closed off areas underneath (for example, inside of the house) and fill the shadow area with blue/gray fog. Issue is fixed if there is another layer of full solid blocks placed under all the stairs, stopping the light from passing through.

Examples attached. Final image (without fog indoors) is after placing the solid blocks under the roof’s stairs.