By clicking on Chat options in the chat window (the three dots in the top right hand corner), the agent has access to additional chat settings, including Follow Ups.
The Follow Ups feature allows agents to automatically forward chats to one or more email address(es). This is done by connecting certain email addresses to a success code. The success code that was added to a chat automatically inserts the email address(es) to the follow-up form. The agent can also add text to the email body. E.g. “Returning customer, needs quick attention!”
How you connect success codes to email addresses is explained here.