JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://cdnjs.cloudflare.com/ajax/libs/modernizr/2.6.2/modernizr.min.js"></script>
<script src="http://rawgithub.com/kangax/fabric.js/master/dist/all.js"></script>
<!-- Based on the tutorial at http://www.html5rocks.com/en/tutorials/dnd/basics/ -->
<div id="images">
    <img draggable="true" src="http://i.imgur.com/8rmMZI3.jpg" width="250" height="250"></img>
    <img draggable="true" src="http://i.imgur.com/q9aLMza.png" width="252" height="295"></img>
    <img draggable="true" src="http://i.imgur.com/wMU4SFn.jpg" width="238" height="319"></img>
</div>

<!-- NOTE: Fabric.js sets both the <canvas> element and the wrapper element which it
creates to be user-unselectable using CSS properties (e.g. for Webkit, this is 
-webkit-user-select: none;). We could remove that property during the dragging, but 
I'm just going to wrap the canvas in a container and bind events to that, which is 
less intrusive.
 -->
<div id="canvas-container">
    <canvas id="canvas" width="800" height="600"></canvas>
</div>

CSS

#canvas-container {
    position: relative;
    width: 800px;
    height: 600px;
    box-shadow: 0 0 5px 1px black;
    margin: 10px auto;
    border: 5px solid transparent;
}
#canvas-container.over {
    border: 5px dashed cyan;
}
#images img.img_dragging {
    opacity: 0.4;
}
/* 
Styles below based on  http://www.html5rocks.com/en/tutorials/dnd/basics/ 
*/

/* Prevent the text contents of draggable elements from being selectable. */
[draggable] {
    -moz-user-select: none;
    -khtml-user-select: none;
    -webkit-user-select: none;
    user-select: none;
    /* Required to make elements draggable in old WebKit */
    -khtml-user-drag: element;
    -webkit-user-drag: element;
    cursor: move;
}

JavaScript

/* Drag and Drop code adapted from http://www.html5rocks.com/en/tutorials/dnd/basics/ */

var canvas = new fabric.Canvas('canvas');

/* 
NOTE: the start and end handlers are events for the <img> elements; the rest are bound to the canvas container.
*/

function handleDragStart(e) {
    [].forEach.call(images, function (img) {
        img.classList.remove('img_dragging');
    });
    this.classList.add('img_dragging');
}

function handleDragOver(e) {
    if (e.preventDefault) {
        e.preventDefault(); // Necessary. Allows us to drop.
    }

    e.dataTransfer.dropEffect = 'copy'; // See the section on the DataTransfer object.
    // NOTE: comment above refers to the article (see top) -natchiketa

    return false;
}

function handleDragEnter(e) {
    // this / e.target is the current hover target.
    this.classList.add('over');
}

function handleDragLeave(e) {
    this.classList.remove('over'); // this / e.target is previous target element.
}

function handleDrop(e) {    
    // this / e.target is current target element.

    /*
    if (e.stopPropagation) {
        e.stopPropagation(); // stops the browser from redirecting.
    }
    */
    
    e.stopPropagation(); // Stops some browsers from redirecting.
    e.preventDefault(); // Stops some browsers from redirecting.

    // handle desktop images
    if(e.dataTransfer.files.length > 0){
               
        var files = e.dataTransfer.files;
        for (var i = 0, f; f = files[i]; i++) {
            
            // Only process image files.
            if (f.type.match('image.*')) {            
                // Read the File objects in this FileList.
                var reader = new FileReader();
                // listener for the onload event
                reader.onload = function(evt) {
                    // create img element
                    var img = document.createElement('img');
                    img.src= evt.target.result;                        
                    
                 ...