Apple debuted the MailKit framework with macOS Monterey in 2021, allowing programmers to create cutting-edge and safe additions to the Mail app on the Mac. Extensions may be developed to filter information, send messages, enhance security, and other functions.
In response, Apple stated that legacy Mail app plug-ins would no longer be supported in a subsequent macOS release, and it appears that time has come. Today, AltStore announced that it obtained confirmation from Apple during WWDC last week that macOS Sonoma does not enable plug-ins and that MailKit-based extensions are the only viable alternative going forward.
AltStore revealed in a tweet that it has been confirmed at the WWDC labs that macOS Sonoma does not support legacy Mail plug-ins. Moving future, only MailKit-based extensions are supported.
Once you update, AltServer’s Mail plug-in will no longer function, but we’re working on a new approach that we hope to make available soon.
Not all plug-ins may survive as extensions even though MailKit extensions are more secure and have less functionality than older plug-ins.
Since the first macOS Sonoma beta, legacy plug-ins cannot be opened in the Mail app. The public will receive the update later this year.
