Mob drops from the same sequence have random durability

Mobs will always drop items with the same sequence on the same seed, but this does not apply to the durability level of natural equipment. To reproduce:

1. Use the seed -6365024550271055859
2. Spawn drowned until you find one holding a trident
3. Kill the drowned holding the trident
4. Repeat steps 1, 2, and 3 in another world
5. Notice that tridents from the same seed and sequence have different durability