The fishing bobber is likely invisible because the entity type is removed from the registry here and is not re-added it to the registry. This entity was likely missed since it has the same id as a pig and is one of the ones spawned from a EntitySpawnS2CPacket instead of a MobSpawnS2CPacket.

What the heck, the fishing hook entity was not in EntityList in 1.12. Are there any other such entities I should be aware of?