_layouts/default.html

<!DOCTYPE html>
<html>
{% include head.html %}

<body>
	{% include header.html %}
	<main>
		{{ content }}
	</main>
	{% include footer.html %}

	<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
	<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js" integrity="sha384-ZMP7rVo3mIykV+2+9J3UJ46jBk0WLaUAdn689aCwoqbBJiSnjAK/l8WvCWPIPm49" crossorigin="anonymous"></script>
	<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js" integrity="sha384-ChfqqxuZUCnJSK3+MXmPNIyE6ZbWh2IMqE241rYiqJxyMiZ6OW/JmZQ5stwEULTy" crossorigin="anonymous"></script>
	<script src="https://unpkg.com/commentbox.io/dist/commentBox.min.js"></script>

	<script>
	  // When the user scrolls down 20px from the top of the document, show the button
	  window.onscroll = function() {scrollFunction()};

	  function scrollFunction() {
	      if (document.body.scrollTop > 100 || document.documentElement.scrollTop > 20) {
	          document.getElementById("myBtn").style.display = "block";
	      } else {
	          document.getElementById("myBtn").style.display = "none";
	      }
	  }

	  // When the user clicks on the button, scroll to the top of the document
	  function topFunction() {
	      document.body.scrollTop = 0;
	      document.documentElement.scrollTop = 0;
	  }

		import commentBox from 'commentbox.io';
		// or
		const commentBox = require('commentbox.io');
		// or if using the CDN, it will be available as a global "commentBox" variable.

		commentBox('my-project-id');

	</script>

</body>


</html>