Convert RichText to HTML in PHP API
eZ Platform stores Rich Text internally in XML. To convert this XML to HTML markup common in web projects, you can use this API:
$xhtml5Converter = $this->container->get('ezpublish.fieldType.ezrichtext.converter.output.xhtml5');
$xml = $view->getContent()->getFieldValue('content')->xml;
$html = $xhtml5Converter->convert($xml)->saveHTML();
echo $html;