When standing near a chunk border, specifically south of it and try to look in a way that only a small part of the side of your screen sees the chunk north of you, that particular chunk won't get rendered. Entities are still visible though. It also only works when under the ground. In the video "Minecraft 2019.05.24 - 13.51.30.03.mp4" you can see that it only happens when that block is there and the chunk is visible again when you remove that block. My FOV is set to 100. But the invisible chunk is still noticeable when using a FOV of 70 (normal).