In 2012, Apple added Gatekeeper to Mac OS X (now macOS). When you try to run Mac software downloaded from the internet, Gatekeeper checks whether the software was signed with a valid Developer ID certificate. If not, then Gatekeeper refuses to run the software. Over the years, Gatekeeper has become more strict, recently adding a notarization requirement. On macOS Catalina, Gatekeeper not only chec