Hello I have now compared the two patch sets. They seem very similar but I think yours is a little bit nicer in all respects except I prefer my use of "g_mime_message_get_all_recipients (reply) == NULL". However, one case that is slightly less clear with my approach is what to do about reply-to-thread (or indeed any reply to more than one message). I did not add a reply-to-thread not_all option as I wasn't sure what it should do. Perhaps we could even make reply-to-one return an error if the search gives more than one message? Best wishes Mark