When you click on your name area to go into the inventory screen, the tab labeled "Inventory" is selected as the default tab. When you click the "Avatar" tab, your health pots change to the same number of mana pots that you have.

example is if you have 5 health pots and 18 mana pots... when this bug is encountered it shows that you have 18 health and 18 mana

this is only cosmetic though as when you switch off of this tab, everything goes back to normal so you don't actually get extra health pots.