Mathematics, programming, and a little bit of my life.
Problem: I cannot connect to gmail via Thunderbird with 2 step verification.
Problem: When I try to connect to google mail via Thunderbird, Enter credential for my_email_account dialog shows up, but I cannot push the `Next' button. Well, I can push it, but nothing happens.
It seems the authentication method "OAuth2" related with this problem. Solution: Authenticate with "Normal password", using the google app password, not use the google account password, and watch the connection activity to check the any suspicious activities.