PHPMailer OAuth2 - Add support for Google's XOAuth2

It might be better to use Google's API to send emails. This seems to be the way many email providers are going.

The modules GMail → and Google API client → would be worth looking into.

Many email services are recommending the use of their APIs instead of SMTP for sending email. The Pantheon hosting platform also recommends this approach.

There are a few modules for specific services.

• Sendgrid →
• Mailgun →
• Mailchimp Transactional →
• Gmail API →
• Microsoft Graph API Mail system → (dev release only)
• Mailjet →
• Postmark →
• SendinBlue →
• Amazon SES →

I'm unlikely to work on this any time soon.

Another module which works with PHPMailer SMTP → and OAuth2 Client → is Gmail OAuth2 Client.