macOS 10.15 Catalina is ruthless about launching unknown apps. Unless your app comes direct from the App Store, or the app’s developer got the app notarized by Apple, it won’t launch. Double click on it, and you’ll see a warning — and nothing else. There’s no option to say you trust the app and launch it despite Catalina’s warnings.
But you can still launch those apps. It’s just that Apple hides the controls in the hope that you’ll give up. It’s petty, and it shows a lack of respect for you, the user. However, it’s also dead easy to fix this problem. Let’s see how to launch any app on macOS Catalina.