This mod enables accessing chat and viewing the states of other players in the lobby while in the inventory, blackmarket, preplanning, Crime․net, skills and perk deck selection screens.
That was a copy-paste from the originals description. As of the version the game is today, we already have a chat in inventory and such, however that doesn't mean there isn't a place to add the chat, such as when looking at the safe house or doing your offshore payday. That being said, not only does it add the chat to some guis, but it also adds states of the players, that are in the lobby with you.
I tried to keep as much as possible of the original code, so what I did is a mess and I wouldn't recommend reading, or trying to learn from it. I usually write tests and such, and then I forget to remove them, or I don't know at the moment what to put instead of them, so it's a mess, but the main thing is, that it atleast works.