You’re welcome! I believe you’re trying to use ng serve to test your element but this is not how you should do it. Elements can only be tested in a “static” way meaning that should import the JS script in a web page then use your custom element and see it work.

Your error indicates that the HTML you’re loading has an app-root and that Angular is trying to bootstrap that element, which should never be the case if Angular is bootstrapped for an individual element.

Google Developer Expert in Angular, Consultant and Trainer at http://www.angulartraining.com

Google Developer Expert in Angular, Consultant and Trainer at http://www.angulartraining.com