Explain how custom elements works internally?

Below are the steps in an order about custom elements functionality,

1. 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.
2. App adds custom element to DOM: Add custom element just like a built-in HTML element directly into the DOM.
3. Browser instantiate component based class: Browser creates an instance of the registered class and adds it to the DOM.
4. 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,

Practical Code Example

// Custom Elements Internal Workflow:
// 1. Browser parser encounters <custom-element>
// 2. Custom Element Registry looks up constructor
// 3. Angular Elements creates ComponentRef and attaches Input/Output bindings
// 4. Component renders inside custom element host