What I expected to happen was...:
Open the UI of the villager in order to trade with him.

What actually happened was...:
When trying to trade with a villager, the UI of said villager quickly opens and then immediately closes, making the trade impossible. This doesn't happen with every villager, but it affects the most part of them. This has happened in a Realm Server, and I've tried to quit and re-enter, but nothing has changed.

Steps to Reproduce:
Simply right click any kind of villager with a profession, and then the glitch occurs.