I have a number of Gmail accounts which I manage using Thunderbird (currently version 91.6.1). All use a POP3 Mail Server and (currently) "SSL/TLS" and "Normal password" as the Security Settings. A couple of days ago I received a message from Google saying that, from 30th May this year, Gmail was requiring two-level authentication and suggesting that I change to OAuth2 - so I've been testing this option in advance of the cut-off date. With "Normal password" changed to "OAuth2" but no other changes I find that when I try to receive mail a Google account login screen is displayed with the appropriate Gmail account name loaded - so far, so good you might say; I was expecting that. However, when I press Next on this screen instead of being asked for my Gmail password, which I was anticipating, all that happens is that the same screen is redisplayed with the account name removed. It looks as if I can't sign in to my Google account, as I assume is required for OAuth2; and eventually I get a "POP3 timed-out" message. Any thoughts / suggestions ? Note I'm not an IT expert - so please phrase any replies accordingly. Many thanks