While in one of my creative worlds, I decided to go under bedrock with night vision for no particular reason. What I learned was that below y=0, the night vision effect turns your screen completely black (not including your hotbar), and when you go into your inventory, everything functions as normal, except all textures for items and blocks are completely black. Along with this, all text renders as black as well, and this continues to the escape menu, strangely, and when you leave your world, all text on the main menu is black as well, making it difficult to navigate. I can't explain why this happens, but I do know that the way to fix this is to log back into a world and go above the void, or to just close minecraft entirely. This bug affects versions 1.15 and above, and I got this information from testing 1.13, 1.13.2, 1.14, 1.14.4 (does not apply), 1.15, 1.16.4 and snapshot 20w49a (does apply).