title: How to write the pop-up HTML in a Crossrider extension?
body: <p>How do you write the pop-up HTML in a Crossrider extension?</p>
  
  <p>What triggers it and how do you add an image, eg if you want to show a logo in the pop-up with some text, do you leave the <code>extension.js</code> since you will be writing all the codes in the pop-up HTML?</p>
  
  <p>I am so confused here.</p>