Edit in JSFiddle

var insertedNodes = [];
// WebkitMutationObserver - chrome, safari
// MozMutationObserver - Firefox
var observer = new MutationObserver(function(mutations) {
 mutations.forEach(function(mutation) {
   for (var i = 0; i < mutation.addedNodes.length; i++)
     insertedNodes.push(mutation.addedNodes[i]);
 })
});
observer.observe(document, { childList: true });
console.log(insertedNodes);