Well your wishes have been fulfilled. Over on GitHub is a page ready designed for you to use!

It's my [SEAuthentication][1] repro.

#What does it do?

![enter image description here][2]
![enter image description here][3]

#How does it work?

The essential code is below. There is a load of CSS to go with it.

<!-- language-all: lang-javascript -->

    <center>
      <p id="token">
          <script>
          window.onload = function() {
            var url = location.href
            var index = url.search(/access_token=/g)
            var access_token = url.substring(index+13,index+37)
            document.getElementById("access-token-c").style.display='none';
            if (index > 18) {
              document.getElementById("token-box").value = access_token;
              
              document.getElementById("access-token-c").style.display = 'block';
            }
          document.getElementById("token-box").select();
          }
        </script>
        <p id="token-description" class="token-title">
          Your access token is:<br>
        </p>
      </p>
      <input id="token-box" type="text" name="token">
      <div id="copy-box" class="token-copy">
        Copy with Ctrl+C
      </div>
    </center>


  [1]: https://github.com/timtjtim/seauthentication
  [2]: https://i.sstatic.net/HLiqi.png
  [3]: https://i.sstatic.net/wKbFS.png