Well, now I started considering uninstalling this update of Discovery and installing the previous version. Because now I noticed that, even if you disable tabbed chats for Plus!, Discovery's this bug still prevents chat windows closing internally which means that you don't see the chat window when you close it but WLM still thinks that it is open
hence it doesn't save the conversation in that window, because WLM saves the conversation while closing the window. Since, there is no way of closing those windows other than exiting Messenger itself, so your conversations after installing Discovery haven't been saved at all by WLM.
A similar problem appears for logging option of Plus!. Although Plus! saves the conversation more recently without the need of closing windows, when you close and reopen the chat window for the same contact, it creates a new file blabla@hotmail.com (2). And this goes on for every reopening the chat window.
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