One of the new arrows that was added in the latest snapshot, spectral arrow, is missing its texture for its 3d model. Instead of looking anything close to how its sprite looks like, its completely purple.
On a side note, the arrows with potion effects also dont have their 3d texture, but instead are using the normal arrow 3d texture. Im not sure if that is intended or not.
Duplicate of MC-82809. Please search before creating new issues.