@frosticek
Is simple, links the chat to the ad id, if the ad is deleted, chat ends there, anyway, it would look good because regardless of whether the seller is online or not, will receive the chat, where it will notify It as soon as you log in to the site.
Or put a hook in the administrative area and can enable chat offline as well!
Would be fantastic and suitable as so if you want to activate it if you do not just disable it!
I see this for me as a great need and most certainly also who buys the plugin!