Put the summary of the bug you're having here

What I expected to happen was...:
To be able to place slabs that are waterlogged and see only the corresponding slab texture from below.

What actually happened was...:
I saw the slab texture, but the water_still.png texture was visible at the same time.

Steps to Reproduce:
1.place a slab of any kind (I used quartz) and put it in the bottom half of a block on land. not in the water, even though it might also work that way. I'm not sure.

2. enclose the slab around the sides with full blocks

3. make the slab watterlogged

4. look at the underside of the slab you placed in step 1.

5. you will now notice that a water texture is visible on the underside of this slab.