Inject modulepreload tags into HTML.
$ npm install --save-dev modulepreload
$ npx modulepreload inject -w index.html
Before injection:
<!-- index.html -->
<html>
<head>
<title>Example</title>
</head>
<body>
<script type="module">
import './dep.js'; // imports ./another-dep.js
</script>
</body>
</html>
After injection:
<!-- index.html -->
<html>
<head>
<title>Example</title>
<link rel="modulepreload" href="/dep.js" />
<link rel="modulepreload" href="/another-dep.js" />
</head>
<body>
<script type="module">
import './dep.js'; // imports ./another-dep.js
</script>
</body>
</html>