When trading with librarians, if you have the proper amount of emeralds, but not a book for the trade, when you click on it, the active trade jumps to the next item (bookshelves).

What I expected to happen was...:
The emeralds to fill in the slot, the book slot and the trade slot to be empty.

What actually happened was...:
A different trade was selected 

Steps to Reproduce:
Be in survival with a stack of emeralds. Trade with a librarian that has a book trade. Click on the book trade.