Below are the steps in an order about custom elements functionality,
App registers custom element with browser: Use the createCustomElement() function to convert a component into a class that can be registered with the browser as a custom element.
App adds custom element to DOM: Add custom element just like a built-in HTML element directly into the DOM.
Browser instantiate component based class: Browser creates an instance of the registered class and adds it to the DOM.
Instance provides content with data binding and change detection: The content with in template is rendered using the component and DOM data. The flow chart of the custom elements functionality would be as follows,
