Expected Behaviour:
While the ring is equipped and I do not have a mana source/the source is empty, I take drowning damage when the air meter empties.

Actual Behaviour:
While the ring is equipped and I do not have a mana source/the source is empty, I do not take drowning damage when the air meter empties. The air meter does not refill, it stays empty but I take no damage from drowning.

While the ring is unequipped I do take drowning damage when my air runs out. I am sure I do not have any mana source on me, as my damaged manasteel armour does not repair itself. When mana is present, the ring works as expected.

Botania: 236
Forge: 10.13.4.1556

Log: https://gist.github.com/Leviathan143/16edc69ca836dfd91e0a