Re: thunderbird gmail notice
OAUTH2 has been in use for several years now, and not only by Google. It is what makes a given application no longer a "less secure app."
I can't imagine how you weren't prompted long ago to use OAUTH authentication except if you had the "less secure apps" option turned ON in your Google Account.
What's described certainly does not qualify as "new news" in any way, shape or form. I do know that at one point, and I can't remember when, I got a notice from Google telling me that they were going to turn "less secure apps" off in all accounts unless the user went in and did something intentional to leave the setting in place. I was using that setting at the time, which was just before Thunderbird and one other e-mail client I used to play with were updated to use modern authentication standards.
Brian - Windows 10 Pro, 64-Bit, Version 1909, Build 18363
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