The bug
If you copy a lectern with a book on it in creative mode and keep its NBT data on the copy (CTRL+Pick block), the copy will have no book on it despite having the NBT for it.
If you copy a lectern with a book on it in creative mode and keep its NBT data on the copy (CTRL+Pick block), the copy will have no book on it despite having the NBT for it.
Likely related to the fact that the lectern has a "
has_book
" state, though its book is saved within its NBT data and is not dropped when broken.