Ever since updating to Sonoma and SpamSieve 3.x I’ve had to rely on the “Check inboxes for new messages not sent to Mail extension” option to filter my mail. That is, until recently, when I unticked “Quit when mail client quits.” Now new messages in my inbox reliably trigger the Mail plug-in. Messages are filtered instantly and that little puzzle piece pops up in my message list. Just a coincidence? If I tick “Quit when mail client quits” again, the plug-in once again fails to trigger. I haven’t made any other changes to my settings.
Yes, I think so. I’ve seen all combinations of the Mail extension working and not working with and without Quit when mail client quits active. All the checkbox does is change a setting. It doesn’t change SpamSieve’s behavior except at the moment when Mail quits. And the Mail bug that sometimes prevents messages from being sent to the extension also affects other Mail extensions not related to SpamSieve.
Well, it’s a happy coincidence if that’s all it is. As long as the extension is working— I called it wrongly a plug-in; I do know the difference — I’m leaving my settings as they are.