Hi dear @Alexey

Thanks for your reply. It was very informative. BTW,

1. Will the corresponding conversation of a Messenger block within a custom page without access restriction also appear on the main Messenger page? Or only those placed within a module's view page (Groups, events, etc)?
2. I find that placing a Messenger block on a module's view page .(i.e. Group's view page) distracts members from the page content a bit. I would like to place it on a separate page within the group, similar to how it's done in Facebook groups. Will that corresponding conversation still appear on the main Messenger page?

Regarding the shoutbox. I got what you mean. Thanks. Just being curious, how did you manage to hide it here on UNA homapage, while still showing it and allowing people to join the chat in Messanger? Have you made some code modifications?

Thanks