X-ray protection does not work below Y=0

Summary:

Below zero, if a player tries to create an x-ray in the usual ways, instead of a black screen, he receives an x-ray.

All methods work:

• Third person view in blocks (eg bulk blocks).
• On entities / boat in blocks (entity / boat in space 1 block high).
• and maybe others that I don't know

Steps to reproduce:

1. Try to reproduce the above x-ray methods above zero.
2. Try to reproduce the above methods of x-ray below zero.

Observed results:

Below zero you will be able to create x-ray, but above zero you will have a black screen instead of x-ray.

Expected results:

Protection against x-ray will work above zero and below.

Image: