Customize/Trigger The Form to Apper When Visitors Reach The End of Article

Add the following snippet at the end of ninja-contact-form.min.js. Or in specific page template wrapped with <script></script> tags.

jQuery(function($){
   var $win = $(window);
   $win.scroll(function() {
   if($win.scrollTop() + $win.height() > $(document).height() - 100) {
       $(window).unbind('scroll');
       window.NinjaSidebar && window.NinjaSidebar.showSidebar($win)
   }
});
})