Minecraft wiki entry for Development_versions, associated text: Crafted in a crafting table as a single column, with a chest in the middle row and a shulker shell both above and below the chest.
In this snapshot, there is a bug that makes the player unable to craft it in the right and left columns.
Works similar to a chest, but keeps its content when broken.
If it has any content inside, it will drop itself in Creative mode as well.
Cannot be placed inside another shulker box.
When hovered over in the inventory, it will show up to 5 slots of its content.
Breaks when being pushed by a piston.
Uses the same opening and closing animations as the shulker.
Can be placed on different sides of a block to open in different directions.
When opening, its hitbox changes from 1 block to 1.5 blocks in its opening direction.
Because of this, it will not open if there is a block of any kind within the closest half-block area in its opening direction.
Can be dyed in any of the available dye colors.
Dyed shulker boxes have a slightly darker bottom part than the normal one.
In this snapshot, there is a bug with obtaining the dyed versions, so currently it is only possible to get them through Creative or commands.
Dispensers will place the block on the ground.
Can be mined with anything, but is mined faster with a pickaxe.