Attach a popup to a marker instance | TrackAsia GL JS Docs

Attach a Popup to a Marker and display it on click.
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>Attach a popup to a marker instance</title>
<meta name="viewport" content="initial-scale=1,maximum-scale=1,user-scalable=no" />
<script src="https://unpkg.com/trackasia-gl@1.0.5/dist/trackasia-gl.js"></script>
<link href="https://unpkg.com/trackasia-gl@1.0.5/dist/trackasia-gl.css" rel="stylesheet" />
<style>
	body { margin: 0; padding: 0; }
	#map { position: absolute; top: 0; bottom: 0; width: 100%; }
</style>
</head>
<body>
<style>
#marker {
background-image: url('https://docs.track-asia.com/assets/Opera_Ho_Chi_Minh.jpeg');
background-size: cover;
width: 50px;
height: 50px;
border-radius: 50%;
cursor: pointer;
}
 
.trackasiagl-popup {
max-width: 200px;
}
</style>
 
<div id="map"></div>
 
<script>
var opera = [106.70327,10.776694];
var map = new trackasiagl.Map({
container: 'map',
style: 'https://maps.track-asia.com/styles/v1/streets.json?key=public_key',
center: opera,
zoom: 16
});
 
// create the popup
var popup = new trackasiagl.Popup({ offset: 25 }).setText(
'The Opera Ho Chi Minh City, by Diego Delso, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=30088100'
);
 
// create DOM element for the marker
var el = document.createElement('div');
el.id = 'marker';
 
// create the marker
new trackasiagl.Marker(el)
.setLngLat(opera)
.setPopup(popup) // sets a popup on this marker
.addTo(map);
</script>
 
</body>
</html>