Barrier Texture Overlap Glitch
If you place barrier blocks and hold the item so the textures appear, any overlapped textures both continuously attempt to place themselves in the front, causing flashing effects.
UPDATE: Viewing water through the texture also derps and shows the water in a weird way (see screenshot 3.)
How to Reproduce:
1. Place a cube of barrier blocks (can be 2x2)
2. Look down upon the blocks
3. Observe for a few seconds.