When signing a 4D app, you may or may not have come across an xcrun error related to an invalid active developer path as shown below:

xcrun: error: invalid active developer path (/Library/Developer/CommandLineTools), missing xcrun at: /Library/Developer/CommandLineTools/usr/bin/xcrun

In this case, this error often means that the Xcode Command Line Tools is not installed or is on an outdated version. To address the error, simply run the command line below to re-register the Xcode toolkit and upgrade to the latest version.

xcode-select --install

If the error still occurs, you can try forcibly resetting it.

sudo xcode-select --reset