I am not sure if this works as intended or if this is a true bug but here goes. I was playing on Minecraft pocket Edition and decided to name some of the villagers with name tags. Also wanted to see if the name tags stayed as they are intended.

What I expected to happen:
I expected the name tags to stay on mobs when you name them.

What really happened:
While playing I decided to test out the Grumm and Dinnerbone name tags on villagers that I didn't want to de-spawn. They flipped upside down as intended but when I saved and quit and relogged into the game that had them in it the name tags were gone and the villagers were upright again. The thing that bugged me is I named another Villager Map Maker and the name stuck. So I knew to report this.

Steps to reproduce:
1. Find a village in a mcpe seed .
2. Name two of the villagers using Grimm and Dinnerbone on the name tags. Name a third anything you want to (I used Map Maker on a coligrapher (or map maker) as an example.)
3. Save and quit.
4. Relog into the game that had the named villagers in it.
5. You will see the Dinnerbone and Grumm name tags are gone but not the third named villager.

I will upload a video to YouTube that I made regarding this so you can see how to reproduce this and put the link below in a comment.