980897 - Yahoo and POP3 not working?
bugzilla.mozilla.org › show_bugBecause, while adding yahoo account, the default option is checked POP3 (in setup window). So, yahoo cant be added with POP3 option, and users have to choose IMAP. But many users, including me, had no idea of this issue, and think, that thunderbird had problems with yahoo. then installed other Mail client. the same problem.