<!DOCTYPE html>
<html>
<head>
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta charset="UTF-8">
  <title>respass</title>
  <link rel="icon" type="image/png" href="/logo.png" />
  <meta name="twitter:card" content="summary" />
  <meta name="twitter:site" content="@respass_chat" />
  <meta name="twitter:title" content="respass" />
  <meta name="twitter:description" content="respass: Open source, community-driven real-time chat engine. Enjoy the chat by clicking the link!" />
  <meta name="twitter:image" content="https://respass.sketch-glass.io/logo.png" />
</head>
<body>
  <script src="./bundle.js"></script>
  <div id="app"></div>
</body>

<!DOCTYPE html>
<html>
<head>
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta charset="UTF-8">
  <title>respass</title>
  <link rel="icon" type="image/png" href="/logo.png" />
  <meta name="twitter:card" content="summary" />
  <meta name="twitter:site" content="@respass_chat" />
  <meta name="twitter:title" content="respass" />
  <meta name="twitter:description" content="respass: Open source, community-driven real-time chat engine. Enjoy the chat by clicking the link!" />
  <meta name="twitter:image" content="https://cdn.rawgit.com/sketchglass/respass/master/ui/dist/logo.png" />
</head>
<body>
  <script src="./bundle.js"></script>
  <div id="app"></div>
</body>

Use rawgit link as twitter:image
Use rawgit link as twitter:image
