Attempting to set up a yahoo email in thunderbird 140.9.0esr(64-bit). The goal is to have this set up on multiple workstations, so I've made the adjustments recommended per this article: https://support.mozilla.org/en-US/kb/thunderbird-and-yahoo#w_please-check-the-following-before-asking-for-support So, the toggle for mailnews.oauth.usePrivateBrowser is set to true, site/third-party cookies are always allowed (no exceptions), and the authentication method is set to OAuth2. Using the recommended server settings for yahoo: imap.mail.yahoo.com : 993 smtp.mail.yahoo.com : 465 I am able to set up the initial OAuth. The window pops up, I log in using the account password then put in the texted code, then the window closes and I get an email confirming the login. Hitting done within Thunderbird after this has it check the password again, and it fails: "Unable to log in at server. Probably wrong configuration, username or password." This is on a fresh Windows 11 install/fresh Thunderbird install.