Detect added element to DOM with Mutation Observer

I'm adding some element to DOM after drag event. I need to detect this element and the moment when this element was added. I use Mutation Observer but something is wrong, the code:

var targetNodes = $('.mvly');
var MutationObserver = window.MutationObserver || window.WebKitMutationObserver;
var myObserver = new MutationObserver (mutationHandler);
var obsConfig = { childList: true, characterData: true, attributes: true, subtree: true };

targetNodes.each(function(){
    myObserver.observe(this, obsConfig);
} );

function mutationHandler (mutationRecords) {
    mutationRecords.forEach ( function (mutation) {
        if (typeof mutation.addedNodes == "object") {
            console.log('test');
        }
    });
}

Can anybody help, much thx.