Oh crap. Gmail is deprecating support for picking up mail from a remote server using POP3 polling in January 😠Given that I switched to this mode due to reliability problems with direct delivery via mail forwarding, this really sucks...
@jmason@nelson I read email in Thunderbird through imap. Some strange things with folders (which are in reality tags thus mails are in several folders, and if you delete a mail in another folter than "all mail" it is not deleted...