One thing that's both cool and kind of scary about Twitch is it keeps your message history from all live chats for all time, and by using extensions you can easily view them. If the VOD is active, you can even click on your message and it will jump to exactly that point in the VOD.
So on one hand cool, can go back and see some nice moments. On the other hand, if your account is more than a few years old and you've ever missed a vibe check, sent a joke that didn't land, a cringe moment - All of that comes up too. Streamers can also see all of your history, even from past streams.