'CurrentLoggedOnUserName' instead of 'Guest'

Hi there, 

One of the main parts in our IT Support is this chat box. And when the user/client sees 'Guest' as a representative of him, it looks very unprofessional.

Can an option be added please for this 'Guest' to feed the 'current-logged-in-user'? I'm not asking for it to be default, just an option in the Settings.

Thanks.