Index: /CKEditor/trunk/CHANGES.html
===================================================================
--- /CKEditor/trunk/CHANGES.html	(revision 5963)
+++ /CKEditor/trunk/CHANGES.html	(revision 5964)
@@ -76,4 +76,5 @@
 		<li><a href="http://dev.ckeditor.com/ticket/6083">#6083</a> : Dialog close sometimes cause collapsed editor selection before the insertion.</li>
 		<li><a href="http://dev.ckeditor.com/ticket/6253">#6253</a> : BIDI: creating a Numbered/Bulleted list causing improper behavior on bidi.</li>
+		<li><a href="http://dev.ckeditor.com/ticket/4023">#4023</a> : [Opera] Maximize plugin.</li>
 		<li>Updated the following language files:<ul>
 			<li><a href="http://dev.ckeditor.com/ticket/6427">#6427</a> : Ukrainian;</li>
Index: /CKEditor/trunk/_source/plugins/maximize/plugin.js
===================================================================
--- /CKEditor/trunk/_source/plugins/maximize/plugin.js	(revision 5963)
+++ /CKEditor/trunk/_source/plugins/maximize/plugin.js	(revision 5964)
@@ -195,4 +195,12 @@
 
 							// Hide scroll bars.
+							var viewPaneSize = mainWindow.getViewPaneSize();
+							var styles = 
+								{
+									overflow : 'hidden',
+									width : ( CKEDITOR.env.opera ? viewPaneSize.width : 0 ) + 'px',
+									height : ( CKEDITOR.env.opera ? viewPaneSize.height - 16 : 0 ) + 'px'
+								};
+							
 							if ( CKEDITOR.env.ie )
 							{
@@ -202,11 +210,10 @@
 							else
 							{
-								mainDocument.getBody().setStyles(
-									{
-										overflow : 'hidden',
-										width : '0px',
-										height : '0px'
-									} );
-							}
+								mainDocument.getBody().setStyles( styles );
+							}
+							
+							// #4023: [Opera] Maximize plugin
+							if ( CKEDITOR.env.opera )
+								mainDocument.getBody().getParent().setStyles( styles );
 
 							// Scroll to the top left (IE needs some time for it - #4923).
@@ -216,5 +223,4 @@
 
 							// Resize and move to top left.
-							var viewPaneSize = mainWindow.getViewPaneSize();
 							container.setStyle( 'position', 'absolute' );
 							container.$.offsetLeft;			// SAFARI BUG: See #2066.