With thunderbird, I can sync most anything, mail (imap), calendars and tasks (nextcloud and davdroid), but not nntp/usenet. I use mostly my main computer at home, and my laptop when outside. When I open my laptop, I get a lot of "unread" post on my Usenet accounts. I should be great is thunderbird could add the list of newsgroups and the ID of read messages to the sync info that firefox share thanks jdd