Ears of an invisible armadillo do not render when viewed from behind

The ears of an invisible armadillo will not render when viewed in spectator mode, or when the entity is on the same team as the player.

Steps to Reproduce:

1. Spawn an armadillo

2. Make it invisible:

   /effect give @e minecraft:invisibility infinite

3. Change gamemode to spectator

Observed Behavior:

The ears of the armadillo will not be visible when viewed from behind.

Expected Result:

The ears of the armadillo would be visible at all times, regardless of the entity's effects, or the gamemode the player is in.

Fix:

One possible fix is to copy the texture of the 2D plane to the opposite side. This does cause z-fighting, likely due to another underlying issue.