Thanks Joost! Could you please elaborate on the type of message you would like to send?
At this moment it is not possible for a website visitor to "close" the chat, other than to leave the website. At that moment, for the agent, the visitor appears to be offline.
On the other side, if an agent choses a website chat conversation, the visitor always sees "Chat closed by agent".
Actually, I think that would be indeed helpful to get a status: user has left chat (when he closes it, or closing the webpage). We have faced plenty of times that chat is still needed, status shows offline, but just because user currently on another webpage.
Also, would be handy to add a possibility for the user from his side (sort of button) - leave a chat, or close