Ive Got A Weird Book On Cubecraft Hub, WTF ?!?!

[:Flix242]

I don't really know what happened but I got that weird glitchy book from nowhere instead of the present to gift ranks to others.
Ive looked what was written inside the book and there was literally nothing inside, just a single page with nothing in it.
The only strange thing that Ive did before getting the book was swimming very far away from the lobby and then, got tp-ed back to spawn with it in my hotbar (even if I don't really know when I got it exactly because I wasn't watching my hotbar every 5 seconds).
Ive asked peoples in the chat if they had a book too and 3 of them said "yes" in a row but Ive asked again 5 minutes later and they didn't even responded to me so I don't know if they were lying or not.
Then, I left the server and reconnected and the book has disappeared without any particular reason.
I don't know if this is a bug/glitch, a extremly rare easter egg if you go too far from the lobby or a mod that trolled me or just tried to scared me.
If anybody has any ideas or explanation of what the heck is this thing or any theories, please, comment them.

Proof Image of the book (look at the hotbar) :

 

[Matriox]

pretty sure that book contains a brief description of recent updates, maybe its a bug that nothing was in it. well I'm speaking from a java point of view not sure if its the same on bedrock

 

[ENDERIUM]

What I'm concerned about is how the Summer Bundle menu opens up when you win/lose a game. It should be replaced with something like Plants.