Mobs with the Pickup Ability can delete random equipment

When a mob with the ability to pick up items takes a full set of armor in closely packed clump(s) (similar to an item stack and/or next to another pile/stack) in the same tick (simultaneously or all at once), it doesn’t equip all 4 pieces, resulting in loss.

Steps to Reproduce:

1. Build an enclosed space, using material that can block the mobs' line of sight &/or pathfinding, ideally glass or non-full blocks, like stairs, in a 1×2×1 space.

2. Drop a full set of armor of any combination of any type in the enclosed space. It is important to do this before spawning mobs. (Dropping a bunch of randomly stacked items in the same block space increases the chances of the bug occurring.)

3. Summon/Spawn 1 mob at a time inside enclosed space until one picks up the dropped items.

Expected Result: The mob equips all pieces of the dropped armor & has 1 item in their hand, following their preferences (Zombie: random item < shovel < sword < etc).

Observed Result: The mob equips a random number of armor less than 4 on random parts of their body, deleting some items in the process.

​Other Notes:

• Doing this with a mob spawned wearing armor further speeds up the item loss.

• Doing this in continuous mob succession will eventually delete every piece of equipment.