Index: /CKEditor/trunk/_source/plugins/selection/plugin.js
===================================================================
--- /CKEditor/trunk/_source/plugins/selection/plugin.js	(revision 5774)
+++ /CKEditor/trunk/_source/plugins/selection/plugin.js	(revision 5775)
@@ -175,5 +175,5 @@
 							editor.on( 'blur', function( evt )
 							{
-								editor.document.$.selection.empty();
+								editor.document && editor.document.$.selection.empty();
 							});
 						}