<!-- 
// HTML 
// 22 feb 2017
// Only Bootstrap Modal (#myModal) is used in the javascript. 
Everything else is optional. See the JS. 
-->

<h4>Bootstrap Modal with SessionStorage</h4>
<hr />
<p class="desc">
  Click this button to <strong>Refresh</strong> the page.
</p>
<a href="" id="refresh-page" class="btn btn-info btn-sm">
  Refresh Page
</a>

<p class="desc">
  Click this button to <strong>Reset</strong> and <strong>Refresh</strong> the page. 
</p>
<a href="" id="reset-session" class="btn btn-warning btn-sm">
  Reset Session
</a>

<!-- Bootstrap Modal -->
<div class="modal fade" id="myModal" role="dialog">
<div class="modal-dialog">
<!-- Modal content -->
<div class="modal-content">
<!-- Modal header -->  
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal">&times;</button>
<h4 class="modal-title text-primary">Victor Frankenstein</h4>
</div>
<!-- Modal body -->  
<div class="modal-body">
<p>
  Victor is a modern scientist unleashed upon an unsuspecting society. Not fully aware of the consequences of his creating a new race of humans, he spends his entire life trying to destroy the same creation. Victor is also the unbridled ego who must satisfy his urge to know all and use that learning to create a new race of man. His excesses ultimately destroy him. Victor represents the id, the part of the psyche that is governed by the instinctive impulses of sex or aggression.
</p>
</div>
<!-- Modal footer -->  
<div class="modal-footer">
<button type="button" class="btn btn-default btn-sm" data-dismiss="modal"> Close </button>
</div>
</div> <!-- // .modal-content -->
</div> <!-- // .modal-dialog -->
</div> <!-- // #myModal -->
// CSS is only for the visual design of this page. This got nothing to do with the storages. See the JS.
// 22 feb 2017

$text: #FFD5C2;
body {
  background-color: #335C64; 
  margin:10px;
  h4 {
    color: $text;
    }
  .desc {
    color: $text;
    margin-bottom: 4px;
    }
  .btn-sm {
    margin-bottom: 15px;
  }
}


View Compiled
// Original code by Simon. You can check the original code here https://codepen.io/html5andblog/pen/qEqdqO?editors=1010
// Altered and Edited for Bootstrap Modal
// 22 feb 2017

// init
jQuery(document).ready(function(){

  // Start
  // sessionStorage.getItem('key');
  if (sessionStorage.getItem("story") !== 'true') {
    // sessionStorage.setItem('key', 'value'); pair
    sessionStorage.setItem("story", "true");
    // Calling the bootstrap modal
    $("#myModal").modal();
    }
  // End
  
  // Do not include the code below, it is just for the 'Reset Session' button in the viewport.
  // This is same as closing the browser tab.
  $('#reset-session').on('click',function(){
  sessionStorage.setItem('story','');
  });
});
Run Pen

External CSS

  1. https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.0.0-alpha.6/css/bootstrap.min.css

External JavaScript

  1. https://cdnjs.cloudflare.com/ajax/libs/jquery/3.1.1/jquery.min.js
  2. https://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/4.0.0-alpha.6/js/bootstrap.min.js