Unlimited XP and duplications using a grindstone and book and quill

I don't know if it is actually the 1.14.60 Hotfix, as I have no idea what that means or where to find that information. 

The problem is that you can use an enchanted item to grind forever, keeping the original, receiving XP as though you had used the grinder, and creates unenchanted duplicates of the enchanted item. 

Necessary items: Grindstone, Anvil, Book & Quill x2, enchanted item, & Crafting Table
Create a signed book using one book and quill. Content does not matter, but include an author, title and text (unsure if lack of one of these prevent the bug from occurring). This doesn't work on Xbox one (maybe a separate issue — doesn't create a book when you hit "Sign"), so you have to write the book on mobile. After writing one book, put it in the crafting table with the second to create a single copy of the original. The bug has now occurred. Now, once you put (we will use the example of an enchanted book with Efficiency II) the book in the grinder, and tap to receive the unenchanted result, instead it throws out one book (as though your inventory were full), the XP is received, and the original Eff. II book remains where it was to become unenchanted again.
A similar thing occurs when you combine two items in an anvil. If I have a Diamond Helmet with Unbreaking II, and I combine it with a book with Aqua Affinity I, a Diamond helmet with Unbreaking II is thrown out (again, as though my inventory were full) and I receive a Diamond Helmet with Unbreaking II and Aqua Affinity I. This is activated by the same thing I described above — creating a copy of a signed book.

This was discovered on YouTube by a brother of mine, and I don't have the link, and was also found on Instagram by a different brother. I don't have a screenshot, but the situation is that we (myself and my brother) were playing on a world on our Xbox One with two iPhones joined onto the world (hosted by the Xbox One account).