has_book lectern block displays do not show a book at all

Run this command: /summon minecraft:block_display ~ ~ ~ {block_state:{Name:"minecraft:lectern",Properties:{"has_book":"true"}}}

A block display that looks like a lectern is created. However, despite has_book being set to true, there is no book to be seen at all.

You can verify that the state is correctly set using /data get entity @n[type=block_display] and checking the output.

Contrast the result of running /summon minecraft:block_display ~ ~ ~ {block_state:{Name:"minecraft:enchanting_table"}} - the enchanting table display created by this command has a book as you’d expect it to.