Cannot call method createDocumentFragment of undefined
Please, read this Documentation: content type
You could not use json as html. You should wrap json to html.What You could do?
Something like this:
$.magnificPopup.open({ items: { src: '<div class="white-popup">Dynamically created popup</div>', // can be a HTML string, jQuery object, or CSS selector type: 'inline' callbacks: { open: function() { $.getJSON("/index.json").done(function( data) { data.each( function(index, value) { $("div.white-popup").append(value); }); }) }, close: function() { // Will fire when popup is closed }});I hope it help.