Adding a digital signature

Apple periodically releases security patches that revoke the certificates (digital signatures) of some "specific" developers. Running applications without a certificate results in an error message and an unexpected termination of this application...

To resolve this error, you will need to sign the application manually or disable SIP  on your Mac

You can sign an application using the standard 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 to the Terminal window.

You can sign the executable 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 to macOS at  developer.apple.com  or  wiki.lazarus.freepascal.org