src/index.html

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta http-equiv="x-ua-compatible" content="ie=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <title><%= htmlWebpackPlugin.options.title %></title>
  <meta name="description" content="<%= htmlWebpackPlugin.options.metadata.description %>">
  <!-- base url -->
  <base href="<%= htmlWebpackPlugin.options.metadata.baseUrl %>">
  <% if (webpackConfig.htmlElements.headTags) { %>
  <!-- Configured Head Tags  -->
  <%= webpackConfig.htmlElements.headTags %>
  <% } %>

  <%= htmlWebpackPlugin.files.webpackManifest %>

  <% if (htmlWebpackPlugin.options.metadata.isDevServer && htmlWebpackPlugin.options.metadata.HMR !== true) { %>
  <!-- Webpack Dev Server reload -->
  <script src="/webpack-dev-server.js"></script>
  <% } %>

  <!-- Async Google Tag Manager: change gtmKey value inside config.prod.conf to your to be your site's ID-->
  <% if (htmlWebpackPlugin.options.gtmKey) { %>
  <!-- Google Tag Manager -->
  <script>(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':
      new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],
    j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src=
    'https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);
  })(window,document,'script','dataLayer','<%= htmlWebpackPlugin.options.gtmKey %>');</script>
  <!-- End Google Tag Manager -->
  <% } %>
  <!-- End Google Analytics -->

  <!-- CSS will be injected by webpack here -->
  <!-- Preload link tags will be injected by webpack here -->

</head>

<body>
<% if (htmlWebpackPlugin.options.gtmKey) { %>
<!-- Google Tag Manager (noscript) -->
<noscript><iframe src="https://www.googletagmanager.com/ns.html?id=<%= htmlWebpackPlugin.options.gtmKey %>"
                  height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript>
<!-- End Google Tag Manager (noscript) -->
<% } %>

  <app>
    Loading...
  </app>

  <!-- Scripts will be injected by webpack here -->
</body>
</html>