Oflline Messages Notification for MUCs
The notification system should be tunable and uniform both for personal 1-on-1 chats and multi-user conferences.
There is a notify_on_all_muc_messages option, which makes Gajim's tray icon blink upon message arriving to the MUCs Gajim user in. So, user is immediately notified when someone talked in the conference.
However, if a user goes online from the offline state and there were some MUC messages during his absence, there is no any notification about it. To know if there were any messages at all, user need to manually check conferences' logs by himself.
This is not the case for user-to-user chats, since there is a notification if a user goes online and have unread messages.
Personal chats and multi-user conferences should have uniform notification settings, there should be some option in Gajim, e.g. notify_on_all_offline_muc_messages, which will enable an offline message notification for MUCs.