Got note drag-and-drop working in WebKit.

static/css/style.css

@@ -3,6 +3,8 @@ html, body {
   background-color: #fafafa;
   text-align: center;
   font-family: sans-serif;
+  -moz-user-select: none;
+  -webkit-user-select: none;
 }
 
 a {
@@ -599,6 +601,7 @@ h1 {
   -moz-border-radius-bottomright: 5px;
   -webkit-border-radius: 5px;
   -moz-user-select: none;
+  -webkit-user-select: none;
   color: #fafafa;
   background-color: #fafafa;
   min-width: 20px;
@@ -910,6 +913,7 @@ h1 {
 
 .pulldown_label {
   -moz-user-select: none;
+  -webkit-user-select: none;
   color: #000000;
   text-decoration: none;
 }

static/js/Editor.js

@@ -784,6 +784,10 @@ Editor.prototype.drag = function( event ) {
       var drop_target = drop_targets[ i ];
       var target_position = getElementPosition( drop_target );
       var target_size = getElementDimensions( drop_target );
+      if ( WEBKIT ) {
+        target_position.x -= viewport_position.x;
+        target_position.y -= viewport_position.y;
+      }
 
       // if the div is wholly above or below the drop target, then it's not overlapping it
       if ( ( div_position.y < target_position.y && div_position.y + div_size.h < target_position.y ) ||