Letter Opener is ready for Mail Extensions, but macOS Mail isn't.
Mail is known to crash when Mail Extensions are enabled. These issues are still present in macOS Sonoma 14.2. Some possible workarounds:
- Disable junk mail filtering.
- In the Mail app, choose Mail > Settings, then click Junk Mail. Disable the checkbox by Enable junk mail filtering.
- Deactivate all rules.
- In the Mail app, choose Mail > Settings, then click Rules. Disable the checkbox of all rules.
These issues can only be addressed by Apple, and not by developers of Mail Extensions. Our friends at Marketcircle have the same problem.
Get notified when these issues get resolved.
Please reports these crashes to Apple. The more reports they get, the more likey it is that these bugs will be addressed.
- Open Console app and select Crash Reports in the sidebar. Then select a Mail crash report at the top of the window. Select all the text of the crash report and copy it.
- Use the Product Feedback Form to submit the crash report.
Alernatively you can use the Feedback Assistant, if you have accces to it.