Good find, I can see that having the simpler logic path being an issue for people looking for a place to tag onto Unequip I will make the changes and post a solution ASAP. The fix will be included in the 1.4 update.
This is by design, when right clicking items when a container is open it overrides the normal logic and will swap the item between the inventory and container. If you look at most MMO’s imagine having your bank storage open. When you right click to use an item it moves the items to and from a container. For example in WoW your backpack is open and your Bank is open. If you right click on a potion it won’t consume the potion it will move it to the Bank or Backpack (depending on where it is located) same goes for equipment. Please feel free to change this logic if it is not what you want in your game