Fatal error: Uncaught eZ\Publish\Core\Base\Exceptions\InvalidArgumentException: Argument '$xmlDoc' is invalid: Transformation of XML content failed: Error in 0:0: runtime error: file /app/ezplatform/app/../vendor/ezsystems/ezplatform-richtext/src/lib/eZ/RichText/Resources/stylesheets/docbook/xhtml5/output/core.xsl line 16 element attribute Error in 0:0: xsl:attribute: Cannot add attributes to an element if children have been already added to the element. Error in 0:0: runtime error: file /app/ezplatform/app/../vendor/ezsystems/ezplatform-richtext/src/lib/eZ/RichText/Resources/stylesheets/docbook/xhtml5/output/core.xsl line 16 element attribute Error in 0:0: xsl:attribute: Cannot add attributes to an element if children have been already added to the element. in /app/ezplatform/vendor/ezsystems/ezplatform-richtext/src/lib/eZ/RichText/Converter/Xslt.php:141 Stack trace: #0 /app/ezplatform/vendor/ezsystems/ezplatform-richtext/src/lib/eZ/RichText/Converter/Aggregate.php(44): EzSystems\EzPlatformRichText\eZ\RichText\Converter\ in /app/ezplatform/vendor/twig/twig/src/Template.php on line 196