My thunderbird account that is authenticated through Oauth2 will not receive or send emails through the service after I changed my Gmail password. When opening Thunderbird, a window appears asking for me to login to my Gmail account by entering my password. After entering my password, it asks for permissions from Gmail and the window closes after clicking "Allow." After this, no emails are received and when attempting to write emails, the same window comes up and the progress bar of the sent mail is stuck and does not process/send, even after following through the instructions in the Gmail login window that pops up. I have tried various solutions that I have found on forums, but none have fixed the issue of Oauth2 authentication not working properly. I have been able to receive emails by using the "Normal password" authentication option in Thunderbird and generating an app password through Gmail, but the same issue with sending emails comes up as it opens a window and asks to login through Gmail again, which leads to the stuck progress bar. Here are other solutions I have tried that I have not had any luck with (running on latest version of Thunderbird): - Toggling "Allow less secure apps" through Gmail (was already enabled prior to problem with Thunderbird) - Setting general.useragent.compatmode.firefox to TRUE in the config editor - Deleting all saved passwords in settings and logging in again Any pointers or workarounds would be greatly appreciated. I was and would content with using an app specific password for Thunderbird considering it fixed part of the problem, but still was unable to send emails.