src/dev-app/index.html

<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title>Angular Material</title>
  <base href="/">

  <link rel="icon" type="image/x-icon" href="favicon.ico">
  <link rel="preconnect" href="https://fonts.gstatic.com">
  <link href="https://fonts.googleapis.com/icon?family=Material+Icons" rel="stylesheet">
  <link href="https://fonts.googleapis.com/css2?family=Roboto:wght@300;400;500&display=swap" rel="stylesheet">
  <link href="theme.css" rel="stylesheet">

  <script>
    if (window.customElements) {
      window.customElements.forcePolyfill = true;
    }
  </script>
  <script src="@webcomponents/custom-elements/custom-elements.min.js"></script>

  <!-- FontAwesome for mat-icon demo. -->
  <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/font-awesome/4.5.0/css/font-awesome.min.css">
</head>
<body>
  <dev-app>Loading...</dev-app>

  <script src="core-js-bundle/index.js"></script>
  <script src="zone.js/dist/zone.js"></script>
  <script src="systemjs/dist/system.js"></script>
  <script src="system-config.js"></script>
  <script src="https://www.youtube.com/iframe_api"></script>
  <script src="https://unpkg.com/@googlemaps/markerclustererplus/dist/index.min.js"></script>
  <script>
    (function loadGoogleMaps(key) {
      var script = document.createElement('script');
      script.src = 'https://maps.googleapis.com/maps/api/js?libraries=visualization' +
        (key ? '&key=' + key : '');
      document.body.appendChild(script);
    })(window.DEV_APP_VARIABLES.GOOGLE_MAPS_KEY);
  </script>
  <script>
    System.config({
      map: {
        // Maps imports where the AMD module names start with workspace name (commonly done in Bazel).
        // This is needed for compatibility with dynamic runfile resolution of the devserver and the
        // static runfile resolution done in the "pkg_web" rule. In the built web package, the output
        // tree artifact serves as workspace root and root of the current dev-app Bazel package.
        'angular_material': '',
        'angular_material/src/dev-app': '',
      }
    });
    System.import('main').catch(console.error.bind(console));
  </script>
</body>
</html>