<head>
  <meta charset="utf-8">
  <title>Application Name</title>
  <meta name="description" content="A description for the application.">
  <meta name="viewport" content="initial-scale=1, minimal-ui, maximum-scale=1, minimum-scale=1" />
  <link rel="shortcut icon" type="image/png" href="favicon.png?v1" sizes="16x16 32x32 64x64">
  <link rel="apple-touch-icon" sizes="120x120" href="apple-touch-icon-precomposed.png">
</head>

<body>
  <div id="react-root"></div>
</body>

<head>
  <meta charset="utf-8">
  <title>Application Name</title>
  <meta name="description" content="A description for the application.">
  <meta name="viewport" content="initial-scale=1, minimal-ui, maximum-scale=1, minimum-scale=1" />
  <link rel="shortcut icon" type="image/png" href="/favicon.png?v1" sizes="16x16 32x32 64x64">
  <link rel="apple-touch-icon" sizes="120x120" href="/apple-touch-icon-precomposed.png">
</head>

<body>
  <div id="react-root"></div>
</body>

Change icon hrefs to the root level.
Change icon hrefs to the root level.

When navigating to a page such as /documents/new the favicon was not available as this file was referencing the image /documents/favicon.png which does not exist.