I was doing Minecraft 1.14 survival and mining coal, while mining coal, I realized that I can see through stone wall, I seen a squad (or if that is called) but I didn't seen water, other stone blocks, or any other cave. only the lava splash heard. to reproduce it is a bit hard, but possible, create a small cave in stone, then move near stone wall and change look render to right/left until you get possibility to see through them. (NOTE: some stone walls may not affect this rendering bug, I tried on a 2x2 stone wall, where right was another wall, and left was air block (nothing) another note: if you think that was an unloaded chunk, you are incorrectly, there are stone blocks in the right, but being near the stone blocks and looking with the face at the margins of the coal blocks, it produced the bug. you will also saw the squad there, but not other caves.