Lavianga's spirits is all kind of bugged.

When you have 2 Laviangas with waistgate, only one is working.
When you die, it sometimes (but not always) stop having it's effect. You have to unequip then reequip it for the flask to work again.
When you have the Azmeri Brew Ascendancy point from the Amazon, it changes the art of the flask, which is sad, because the art is cool.
The word "every" instead of "over" in the description of the effect is a bug. Maybe not an computer bug, but a reality bug. It suggests bursts of instant mana recovery, not a gradual thing. It also then suggest that "flask recovery rate" would not affect it, but it does.

Otherwise, really cool item :)