Index: /CKEditor/trunk/CHANGES.html
===================================================================
--- /CKEditor/trunk/CHANGES.html	(revision 5666)
+++ /CKEditor/trunk/CHANGES.html	(revision 5667)
@@ -58,4 +58,5 @@
 		<li><a href="http://dev.fckeditor.net/ticket/4615">#4615</a> : [IE] Text fields are no longer disrupted in dialog with RTL.</li>
 		<li><a href="http://dev.fckeditor.net/ticket/5887">#5887</a> : The number of columns in the smilies table is now configurable via the smiley_columns setting.</li>
+		<li><a href="http://dev.fckeditor.net/ticket/5100">#5100</a> : It was possible to drag&amp;drop some elements like context menu items or dropdown entries.</li>
 	</ul>
 	<h3>
Index: /CKEditor/trunk/_source/core/dom/element.js
===================================================================
--- /CKEditor/trunk/_source/core/dom/element.js	(revision 5666)
+++ /CKEditor/trunk/_source/core/dom/element.js	(revision 5667)
@@ -1163,4 +1163,5 @@
 				{
 					this.$.style.MozUserSelect = 'none';
+					this.on( 'dragstart', function (evt) { evt.data.preventDefault(); } );
 				}
 			: CKEDITOR.env.webkit ?
@@ -1168,4 +1169,5 @@
 				{
 					this.$.style.KhtmlUserSelect = 'none';
+					this.on( 'dragstart', function (evt) { evt.data.preventDefault(); } );
 				}
 			:
Index: /CKEditor/trunk/_source/plugins/panel/plugin.js
===================================================================
--- /CKEditor/trunk/_source/plugins/panel/plugin.js	(revision 5666)
+++ /CKEditor/trunk/_source/plugins/panel/plugin.js	(revision 5667)
@@ -193,4 +193,5 @@
 
 				holder = doc.getBody();
+				holder.unselectable();
 			}
 			else