CodePen Embed - oNQvoWL

<hello-world></hello-world>

class HelloWorldComponent extends HTMLElement {
  
  constructor() {
    super();
  }
  
  connectedCallback() {
    this.innerHTML = `<h1>Hello world!</h1>`
  }

}

customElements.define("hello-world", HelloWorldComponent)

This Pen is owned by Joseph Safwat Khella on CodePen.

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