Books created in 1.21.5 or prior with "glitched" 15 lines will break in the 1.21.6 update

Books with a glitched line amount being 15 (a books default limit is 14 lines) wil complety break in the 1.21.6 update you cant edit delete op place text on these pages and a scrollbar is visible on the left.

How to reproduce

1. Get a book and Quill in 1.21.5.

2. Open the book and write something like text then hit enter.

3. Now that you have a text and you are on a newline hit ctrl + a to copy all text this will include: text + newline(enter).

4. Then hit ctrl + v till the book is completly filled.

5. You will see that your caret(text cursor) is on the 15th line of the book next to the back arrow (arrow only visible when you are on the second page or further)

6. Now that you have a page with 15 lines click “Done”.

7. Open the word again in 1.21.6

8. Open the Book and Quill.

9. The page you created will have a scrollbar and can't be edited through normal means (ctrl + a then delete will work).

Observed Result:
The page breaks leaving the player unable to fix their page.

Expected result:
The 15th row is removed from the book after the fix was made in 1.21.6 preventing the 15th line from being created, so that the whole page doesnt break.