Players can see through blocks when inside slabs or stairs

The Bug:

Players can see through blocks when inside slabs or stairs.

Steps to Reproduce:

1. Align yourself to the block grid and summon some blocks around yourself by using the commands provided below.

   /execute align xyz run teleport @s ~0.5 ~ ~0.5

   /fill ~-1 ~-1 ~-1 ~1 ~2 ~1 minecraft:sandstone

2. Summon a slab at your eye position by using the command provided below.

   /setblock ~ ~1 ~ minecraft:sandstone_slab[type=top]

3. Look above you and observe your surroundings.

Observed Behavior:

Players can see through blocks.

Expected Behavior:

Players would not be able to see through blocks.