After new years eve I started to notice that all mails to my Kindle suddenly required me to manually accept every delivery by a two-factor authentication by mail.
To wrestle this I decided to change our email delivery service to a self hosted mailcow setup. This way we can automate the required authentication.
But as soon as I did switch to the new email service the two-factor-requirement was removed for my @kindle.com. Well, it solved the problem but made it impossible for me to automate the authentication.
So if anyone of you notice any problems receiving updates from feeder.mobi please let me know at firstname.lastname@example.org or by creating an issue in the Github repo.