Troubleshooting Linux Thunderbird GMail Imap Connection Refused
This Tip Solve the Thunderbird GMail Imap Authentication Failure in GNU/Linux Desktops.
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1. Access Account Settings
First, Choose View Settings for this Account
(If you are still in the Initial Account Creation Wizard then Hit Cancel to Escape)
Like here below:2. Setting Auth Mode
Then Change the Authentication Mode
To Normal Password: