In the last month or so, replies to my emails are not populating according to the date/time, but rather attached to the initial, original email. And worse, the original or responding message does not highlight or show up as NEW/UNREAD in my inbox. That's caused a HUGE problem, as I've missed important work responses, which is affecting my livelihood. ($$) An earlier check into to the problem led me to tweak some settings, to not thread messages. But that hasn't resolved the problem, in that a new, unread reply is NOT showing up as new and in the latest date/time. It should -- ie, it or the original email should show up bold, and with the latest date/time. I've clicked/unclicked the threading icon along the top line but that hasn't resolved it. I've been using Thunderbird for 10+ years, and had never had a problem. Until now. It seems a problem with one of the recent T'bird updates. PLEASE FIX. It should be simple and clear for someone to elect to thread or unthread messages in their inbox, and all of the latest emails should display at the top (or bottom, however you display your emails).