Shulker Box Fill Bar

Shulker boxes should have a "durability" bar showing how full the shulker box is. I would imagine it would be fairly easy to implement because the new bundles have the same sort of functionality. A full bar should represent that every slot in the shulker box is full stack of items. Stacks other than 64, like 16 or non stackable items would count in the same way that they do for the bundle system. This feature would be incredibly useful when determining which shulker boxes are full and which are empty. I store chests full of shulker boxes that are either empty or filled with a specific resource, and being able to see which shulkers are full, and how much, would be very helpful.