Discord rich embed buttons

I made a few discord.py bots, but I came across one which was surprising. It’s called IdleRPG and uses rich embed messages with buttons. Here’s a pic (note the buttons at the bottom of the menu):

I’ve tried contacting the developer and been searching the net but can’t seem to find how they did it. Does anyone know of any resources on how to create them? Please provide links.

I do not use Discord, so this answer is based purely on assumptions and dev instinct.

These buttons look like reactions… they are reactions, right? I mean, just add normal embed, in the callback of the send_message function you can add “buttons” via add_reaction function. And then you can define event listener for message reaction add event and handle the action.