Fatal error: Uncaught Error: Call to undefined method Ressio_HtmlOptimizer_Dom_Element::addChild() in /home/experts1/public_html/wp-content/plugins/psn-pagespeed-ninja/ress/classes/htmloptimizer/dom.php:252 Stack trace: #0 /home/experts1/public_html/wp-content/plugins/psn-pagespeed-ninja/ress/classes/plugin/lazyload/lazyload.php(228): Ressio_HtmlOptimizer_Dom->appendStyleDeclaration('img.lazy,iframe...') #1 /home/experts1/public_html/wp-content/plugins/psn-pagespeed-ninja/ress/classes/dispatcher.php(117): Ressio_Plugin_Lazyload->onHtmlIterateTagBODYAfter(Object(Ressio_Event), Object(Ressio_HtmlOptimizer_Dom), Object(Ressio_HtmlOptimizer_Dom_Element)) #2 /home/experts1/public_html/wp-content/plugins/psn-pagespeed-ninja/ress/classes/htmloptimizer/dom.php(852): Ressio_Dispatcher->triggerEvent('HtmlIterateTagB...', Array) #3 /home/experts1/public_html/wp-content/plugins/psn-pagespeed-ninja/ress/classes/htmloptimizer/dom.php(872): Ressio_HtmlOptimizer_Dom->domProcess(Object(Ressio_HtmlOptimizer_Dom_Element), true) #4 /home/exp in /home/experts1/public_html/wp-content/plugins/psn-pagespeed-ninja/ress/classes/htmloptimizer/dom.php on line 252