If the players head is in contact with water, even if the camera does not look from inside the water, the fog of distance gets the water-color applied.

In this case I stood in flowing water in a cave. The flowing water did touch my players head but did not cover any of my field of view. Still the water-coloring for the fog of distance got applied.

Not that much of a problem, but still an imperfection in visuals

Steps to reproduce

• place a trapdoor underneath a water source block,
• then stand in it
• press space

It's pretty hard to reproduce.