Creakings won't attack the player if they're directly looking to the ground

If a creaking has been summoned or spawned and is tracking the player, the mob won't attack the player if they're looking directly to the ground, even though most of the mob's hitbox is not in the player's sight.

How to reproduce

1. Summon a Creaking.

2. Look at it, then turn around.

3. Look directly at the ground.

Expected result
The mob will follow you and then beat you to death.

Observed result
The mob will follow you, then will stop when close to you.