Fireballs and wind charges shot with a projectile will fly in the direction the player is facing

The bug

If a fireball is shot with bow and arrow, it will not rebounce in the direction it gets hit but rather the direction the player is facing.

How to reproduce

1. Summon a fireball

   /summon fireball ~ ~1 ~ {direction:[0.0,0.0,0.0],ExplosionPower:0}
   

2. Stand fair way away from it (~15 blocks)
3. Shoot an arrow at it, then, before the arrow hits the fireball, quickly look in another direction
   → The fireball will fly in the direction you looked rather than the one you shot the arrow

Video reference: https://gfycat.com/UnitedDistortedGrunion

Code analysis

Code analysis by Marcono1234 can be found in this comment.