/src/main/java/org/htmlunit/html/HtmlElement.java
final boolean mappedElement = getPage( ) && HtmlPage.isMappedElement( htmlPage, qualifiedName) ;
final boolean mappedElement = isAttachedToPage ( ) && HtmlPage.isMappedElement ( htmlPage, qualifiedName ) ;
super.setAttributeNS(namespaceURI, qualifiedName, attributeValue, notifyAttributeChangeListeners, notifyMutationObservers); return; } final String oldAttributeValue = getAttribute(qualifiedName); final HtmlPage htmlPage = (HtmlPage) getPage(); <extra_id_0> if (mappedElement) { htmlPage.removeMappedElement(this); } final HtmlAttributeChangeEvent event; if (ATTRIBUTE_NOT_DEFINED == oldAttributeValue) { event = new HtmlAttributeChangeEvent(this, qualifiedName, attributeValue);