I'm using Drupal 8.
I have a book content type that uses a vocabulary called "book type" as an entity reference field.
I have basic page content type which also uses the the vocabulary "book type" as an entity reference field.
So both of the content types are using the same vocabulary.
What I'm trying to do is filter the books by the chosen book type on the basic page content type, but I just can't figure it out. Here's what I tried.