[macOS] Register a Custom Protocol URL Scheme for my CustomApp

Need help properly registering my CustomApp in macBook Pro running Mojave. I'm trying to "deep link" the CustomApp so it launches a shell script file contained in my app directory when Chrome browser visits customapp://userid@deptid

References:

• https://developer.apple.com/documentation/uikit/inter-process_communication/allowing_apps_and_websites_to_link_to_your_content/defining_a_custom_url_scheme_for_your_app

• https://stackoverflow.com/questions/471581/how-to-map-a-custom-protocol-to-an-application-on-the-mac

App is based on a vendor's SDK needing a bit of customization by running a binary file with additional parameters.

1. Manually created the directory structure /Applications/CustomApp.app/Contents

2. Created Info.plist containing

    <key>CFBundleURLTypes</key>
    <array>
        <dict>
            <key>CFBundleURLName</key>
            <string>Custom App</string>
            <key>CFBundleURLSchemes</key>
            <array>
                <string>customapp</string>
            </array>
        </dict>
    </array>
   

3. Created a shell script that strings together /Applications/CustomApp.app/Contents/MacOS/executable_binary -parameter1 -parameter2 -parameter3

4. Rebooted macBook.

5. Opened Chrome pointing to customapp:// and customapp://userid@deptid but nothing happens.

p.s. I'm not doing any code signing.