Player does not get oxygen when swimming horizontally at the surface

I don't know if this is an intentional feature or not, but when swimming horizontally at the surface of water, you don't get oxygen anymore. I looked at the recent patch notes and they didn't mention anything regarding this.

How to recreate:

1. Sprint underwater to go horizontal.

2. Swim up to the surface, but don't leave the water or your horizontal state. You should normally get oxygen, but you don't anymore.