Ticket #3305: 3305.patch

_source/plugins/selection/plugin.js

@@ -259 +259 @@
          */
         CKEDITOR.dom.document.prototype.getSelection = function()
         {
-                return new CKEDITOR.dom.selection( this );
+                var sel = new CKEDITOR.dom.selection( this );
+                return ( !sel || sel.isInvalid ) ? null : sel;
         };
 
         /**
@@ -319 +320 @@
                                 || ( range.item && range.item(0).ownerDocument != this.document.$ )
                                 || ( range.parentElement && range.parentElement().ownerDocument != this.document.$ ) )
                         {
-                                return null;
+                                this.isInvalid = true;
                         }
                 }
-                
-                return this;
         };
 
         var styleObjectElements =