New Mac - all setup features seem in place, but there’s no Spamsieve functionality in Apple Mail.
I’ve tried complete uninstallation of Spamsieve and reinstall. Full Disk Access is enabled, the extension appears in Mail, but there’s no “Train as Spam” etc
Mail extensions cannot add menu items to Mail. So when using the Apple Mail extension, the SpamSieve commands are in the SpamSieve menu bar icon:
Also, you do not need Full Disk Access.
(When using the Apple Mail plug-in, the commands are instead in the Message menu in Mail, and you do need Full Disk Access.)