I have created a situation where breath is depleting but the gauge is not shown in shallow water.

Expected:
Either gauge is shown or breath does not deplete.

Actual:
The gauge is hidden but still depletes, resulting in unexpected damage.

Reproducing:
Unknown. A world is attached with a block that exhibits the bug.
To show the bug, step in the still water that Steve faces when the world loads. Even though the breath meter is not shown, it is depleting behind the scenes. To show it, press the crouch key and it will appear until Steve stops crouching, but will not refill when he does.