Firefox use HTML5 drag will automatically open the new label solution

Use HTML5 drag, but Firefox will pop up new tags, here is my humble opinion:

Previous online lookup to say use prohibit default event Event.preventdefault ();

But there are still new tags in the code.

Also query that you can set the properties of DataTransfer's SetData to other properties other than text, but I tried

Set to Text/plain or have a new tab to bounce out, but IE will complain: "Accidentally called the method or property access" set into text/html did not bounce out, the same in IE also drag and drop the error: "Accidentally called method or property access"
So say IE only know the Text property, just when I was about to give up compatibility Firefox, tried to suppress the default event globally, really realized.

Document.body.ondrop = function (event) {
        event.preventdefault ();
        Event.stoppropagation ();
    }

Attached to a net to see the pure JS write drag effect feel very good, http://rubaxa.github.io/Sortable/