diff --git a/node_modules/ace_tree/lib/ace_tree/mouse/drag_handler.js b/node_modules/ace_tree/lib/ace_tree/mouse/drag_handler.js
index c4d15cec..d57a285c 100644
--- a/node_modules/ace_tree/lib/ace_tree/mouse/drag_handler.js
+++ b/node_modules/ace_tree/lib/ace_tree/mouse/drag_handler.js
@@ -173,7 +173,7 @@ function initDragHandlers(mouseHandler) {
             
             if (tree.isFocused())
                 tree.renderer.visualizeFocus();
-            tree.renderer.setStyle("ace_tree_DragOver", false);
+            tree.renderer.setStyle("dragOver", false);
             
             dragInfo.target = dragInfo.hoverNode;
             
@@ -192,7 +192,7 @@ function initDragHandlers(mouseHandler) {
     mouseHandler.dragStart = function() {
         mouseHandler.setState("drag");
         tree.renderer.visualizeBlur();
-        tree.renderer.setStyle("ace_tree_DragOver", true);
+        tree.renderer.setStyle("dragOver", true);
         scrollerRect = tree.renderer.scroller.getBoundingClientRect();
         dragInfo = {};
     };
@@ -239,7 +239,7 @@ function initDragHandlers(mouseHandler) {
         
         var selectedNodes = tree.selection.getSelectedNodes();
         var el = document.createElement("div");
-        el.className = tree.container.className + " filetreeDragImage";
+        el.className = tree.container.className + " dragImage";
         var ch = el.appendChild(domNode.cloneNode(true));
         ch.removeChild(ch.firstChild);
         ch.style.paddingRight = "5px";
@@ -269,6 +269,7 @@ function initDragHandlers(mouseHandler) {
         if (dragInfo) {
             if (e.keyCode === 27) {
                 mouseHandler.dragEnd(null, true);
+                event.stopEvent(e);
             } else if (dragInfo && e.keyCode == 17 ||  e.keyCode == 18) {
                 dragInfo.isCopy = e.type == "keydown";
                 dom.setCssClass(dragInfo.el, "copy", dragInfo.isCopy);
diff --git a/plugins/c9.ide.tree/style.css b/plugins/c9.ide.tree/style.css
index 0557ae0c..804046b8 100644
--- a/plugins/c9.ide.tree/style.css
+++ b/plugins/c9.ide.tree/style.css
@@ -119,7 +119,7 @@
     background-position: -5px -1px;
 }
 
-.filetreeDragImage.copy:after {
+.filetree.dragImage.copy:after {
     content: "+";
     background: fade(@selected-focus-background, 92%);
     border: 1px @selected-focus-background solid;
@@ -139,14 +139,14 @@
     background: radial-gradient(5px 5px, circle,  rgb(126, 143, 28), rgb(76, 93, 0));
     box-shadow: 0px 0px 7px 0px #000;
 }
-.filetreeDragImage .toggler {
+.filetree.dragImage .toggler {
     pointer-events: none;
 }
 
-.ace_tree_DragOver.filetree .tree-row.selected {
+.dragOver.filetree .tree-row.selected {
     background: fade(@selected-background, 60%);
 }
-.ace_tree_DragOver.filetree .tree-row.dropTarget {
+.dragOver.filetree .tree-row.dropTarget {
     background: @selected-focus-background;
     box-shadow: 1px 1px fade(@selected-focus-background, 60%) inset;
     color: @selected-color;