I was scrolling through the decor blocks section when I noticed that the Dragon Head icon was placed backwards. Whenever I selected it, it was also placed backwards in my hand. I'm currently in a custom flat world. There is also an odd animation when placing and breaking the heads. Links to my screen shots below.

https://gyazo.com/b6ced80f89bdfdf9829340cfa1001661
https://gyazo.com/c5bd9cd955f793537c779b6f1ab9f4c5
https://gyazo.com/21f91e4077c407073d13eabf32accc6c