If you go into gamemode 3 and click to view the perspective of an shulker, and have torches around you that you can clearly see, if you move your mouse around, the particles on the torch glitch out and move around with your mouse cursor.

How to recreate:

• Spawn a shulker mob.
• Place torches on a wall of any material around the Shulker.
• Go into gamemode 3.
• Click on the Shulker to go into it's perspective.
• Move mouse around
  You'll notice the particles glitching as you move your mouse, as you can see in the attached picture.