What happened:
When you re-texture a block to completely transparent, it creates a visual bug on the block beneath it.
Steps to reproduce:
1-Retexture a block to completely transparent. (CTRL+A, Delete, CTRL+S and done.) (Recommended using a resource pack.)
2-Go to your world.
3-Place that (transparent) block on another block.
This should happen (see the images.)
why is this work as intended? GRUM I'm going to call you now grumtended! 😃