Changes made in the book and quill GUI are not saved upon death

The Bug:

Changes made in the book and quill GUI are not saved upon death.

Steps to Reproduce:

1. Get two players and label them, "Player A" and "Player B".
2. Get "Player A" to write something in a book and quill without closing it.
3. Get "Player B" to kill "Player A".
4. Get "Player A" to pick up the book and quill they dropped upon death and get them to open it.
5. Take note as to whether or not changes made in the book and quill GUI are saved upon death.

Observed Behavior:

Changes made in the book and quill GUI are not saved.

Expected Behavior:

Changes made in the book and quill GUI would be saved.