Index: /CKEditor/trunk/CHANGES.html
===================================================================
--- /CKEditor/trunk/CHANGES.html	(revision 4218)
+++ /CKEditor/trunk/CHANGES.html	(revision 4219)
@@ -68,4 +68,5 @@
 		<li><a href="http://dev.fckeditor.net/ticket/4203">#4203</a> : In IE quirksmode + toolbar collapsed + source mode editing block height was incorrect.</li>
 		<li><a href="http://dev.fckeditor.net/ticket/4387">#4387</a> : Right clicking in Kama skin can lead to a javascript error.</li>
+		<li><a href="http://dev.fckeditor.net/ticket/4397">#4397</a> : Wisiwig mode will cause the host page scroll.</li>
 	</ul>
 	<h3>
Index: /CKEditor/trunk/_source/plugins/wysiwygarea/plugin.js
===================================================================
--- /CKEditor/trunk/_source/plugins/wysiwygarea/plugin.js	(revision 4218)
+++ /CKEditor/trunk/_source/plugins/wysiwygarea/plugin.js	(revision 4219)
@@ -354,5 +354,9 @@
 						}
 						else
-							domDocument.designMode = 'on';
+							// Avoid opening design mode in a frame window thread,
+							// which will cause host page scrolling.(#4397)
+							setTimeout( function(){
+								domDocument.$.designMode = 'on';
+							}, 0 );
 
 						// IE, Opera and Safari may not support it and throw