How do I add chat prefixes to default roblox chat?

I was on Twitch just watching roblox development streams when I saw HeadlessHorror (Owner of Hidden Developers) working on his game with another developer. They managed to edit the default chat to make have a prefix before their name. Some examples of what I saw was...

[DEV] (Username) (Message) and [VIP] (Username) (Message)

I thought that was interesting so I decided to look through the roblox chat scripts using play solo to see how they did it. So far no progress. If somebody is able to help me with this, could you do so? It'd be a great help.

Thanks!