Over the last couple of hours playing Act 2 I had a number of situation where I nearly died because of the health potion cool-down triggering, even if there are no potions in the slot.

I managed to run away, opening the inventory and dragging a stack of the next tier of health potions into the slot, but wasn't able to use it, because of the cool-down which triggered for no reason beforehand.

In SC it's not as dramatic as in HC, but it's frustrating to die because of an UI glitch.

It might also be preferable to have an option to auto-equip the next stack of potions.