+if (browser.isGecko) {
+       Lightbox.prototype.disableDefaultDragging = function(element) {
+               if (!element) {
+                       element = this.grid;
+               }
+               var i, j, name, elements;
+               var elementsNames = ['a', 'img'];
+               for (i=0 ; i < elementsNames.length ; i++) {
+                       name = elementsNames[i];
+                       elements = element.getElementsByTagName(name);
+                       for (j=0 ; j < elements.length ; j++) {
+                               elements[j].draggable=false;
+                       }
+               }
+       };
+}
+else {
+       Lightbox.prototype.disableDefaultDragging = function() {};
+}
+
+
+Lightbox.prototype.onDragStart = function(evt) {
+       var target = getTargetedObject(evt);
+       this.dragged = target;
+       evt.dataTransfer.setData('text', '');
+       target.style.opacity = 0;
+       target.style.width = 0;
+};
+
+Lightbox.prototype.onDragOver = function(evt) {
+       var target = getTargetedObject(evt);
+       while(target.className !== 'slide') {
+               target = target.parentNode;
+       }
+       target = target.parentNode;
+       if (target !== this.dragged) {
+               target.classList.add('dragover');
+       }
+       if (this.previousDragOver && this.previousDragOver !== target) {
+               this.previousDragOver.classList.remove('dragover');
+       }
+       this.previousDragOver = target;
+};
+
+Lightbox.prototype.onDragEnd = function(evt) {
+       this.dragged.style.opacity = 1;
+       this.dragged.style.width = '';
+       if (this.previousDragOver) {
+               this.previousDragOver.classList.remove('dragover');
+       }
+       this.previousDragOver = this.dragged = undefined;
+};
+