On Aug 31st we were made aware of an issue where community mail digests not being delivered.
Our investigation concluded that this was an issue introduced by a change that tightened security for community members. The issue in question was introduced July 25th 2022 and affected customers that had the option to share directly from the digest enabled (`Settings` > `Messages & Email` > `Digest direct share`).
Due to the change on July 25th tokens could no longer be issued to perform a share from the direct share, causing the e-mail to fail entirely.
This bug was in production and impacted all customers with `Digest direct share` enabled from July 25th up to September 1st. On Sep 1st 2022 we introduced a fix to restore the original functionality with the increased security measures still in place.
In addition to applying the fix we set up monitoring to track individual message delivery and the amount of mails that fail to deliver over time. Based on this monitoring alerts were set up to catch delivery issues sooner and on a more granular level.