Codebase Browser
chromium
Go to App

chromium/chrome/test/data/web_apps/subapps_isolated_app/sub1/page.html 

<!DOCTYPE html>
<html>
  <head>
    <title>Sub App 1</title>
    <link rel="manifest" href="./manifest.webmanifest" type="text/html"/>
    <link rel="icon" href="/subapps_icon.png" type="image/x-icon"/>
  </head>
  <body>
    <h1>Sub App 1</h1>
  </body>
</html>