Adding a digital signature MacOS

Apple periodically releases security patches in which it revokes certificates (digital signatures) of some “specific” developers. Running applications without a certificate results in an error message and the application ending unexpectedly…

To resolve the error, you will need to sign the application manually or  disable SIP

You can sign an application using the Terminal utility using the command:  sudo codesign --force --deep --sign - /Applications/NewApp.app
Note that the command includes the path to the application…i.e. After “sign -” you need to put a Space and drag the application into the Terminal window.

You can sign the executable file using the command: sudo codesign --force --sign - /Applications/NewApp.app/Contents/MacOS/NewApp

Press Enter and enter the administrator password.
The password is not displayed when entered into the Terminal, but is entered. After entering the password, press Enter.

Ready! Launch the application.

You can read more about adding a digital signature in macOS at developer.apple.com or at  wiki.lazarus.freepascal.org