These returning guests will either be returned only to you if you are still available, or they will be routed to all available operators. The specific behavior depends on the operator's status and whether or not their chat client sent an invisible command ("gone") back to our servers on window close. The "gone" behavior is completely invisible to the guest.
In general, we've found that it is a little bit better to close a chat (send "gone") so that returning guests are routed to all available operators. This safeguards against situations where you may step away and forget to change your status to away. If a different operator answers the returning guest, the chat can always be transferred back to you if desired. Our native webclient sends "gone," and our Pidgin plugin provides it as an option.
For most services using LibraryH3lp in the usual ways, knowing whether or not the client sends "gone" is not very important, since the routing system will work robustly for ordinary usage in either case. But here is what we know about specific clients:
Clients that send "gone:" the native LibraryH3lp webchat client, Pidgin versions 2.5.9 and lower, Adium versions 1.3.x and lower, and Digsby.
Clients that do not send "gone:" Pidgin versions 2.6.1 and higher, Adium versions 1.4.1 and higher.
Pidgin versions 2.6.1 and higher can send "gone" through an optional plugin.
The Psi client is configurable (General-->Options-->Misc-->Enable inactivity events). Select enable inactivity events to send "gone" and de-select it to not send "gone."
Other clients can easily be tested to determine their status by setting up a chat test. Contact us if you'd like us to test a specific client.