Comment by nickwrb

https://auth-email.com

OAuth is here to stay for major email providers (Outlook, Gmail, etc). Microsoft is dropping support for standard/basic authorization in April 2026, and Google has already done this. But plenty of devices and systems don't (and may never) support OAuth.

Auth-Email is a relay that lets you continue using traditional email auth methods even when your provider requires OAuth. Lots of other more advanced features too: all OAuth grant types, add-ins to modify behavior and lots more.