Ticket #5780: 5780.patch

_source/core/dom/range.js

@@ -1789 +1789 @@
                  */
                 getEnclosedNode : function()
                 {
-                        var walkerRange = this.clone(),
-                                walker = new CKEDITOR.dom.walker( walkerRange ),
+                        var walkerRange = this.clone();
+
+                        // Optimize and analyze the range to avoid DOM destructive nature of walker. (#
+                        walkerRange.optimize();
+                        if ( walkerRange.startContainer.type != CKEDITOR.NODE_ELEMENT
+                                        || walkerRange.endContainer.type != CKEDITOR.NODE_ELEMENT )
+                                return null;
+
+                        var walker = new CKEDITOR.dom.walker( walkerRange ),
                                 isNotBookmarks = CKEDITOR.dom.walker.bookmark( true ),
                                 isNotWhitespaces = CKEDITOR.dom.walker.whitespaces( true ),
                                 evaluator = function( node )