AltPlugin

AltPlugin is a Mail bundle component, which means it is updated through Apple Mail itself rather than as a standalone product. A native Apple Silicon build has been confirmed in our community, so the vendor has already shipped Universal Binary support. To get the native version: update Apple Mail to the latest version by going to System Settings → General → Software Update and installing any available macOS updates. Mail is bundled with macOS and automatically receives native Apple Silicon builds as part of each new macOS release. After updating macOS, your Mail bundle extensions — including AltPlugin — will automatically load the native builds. You do not need to reinstall AltPlugin separately; it will be picked up automatically once Mail itself is on a current native version.