Elementor – Critical Error on WooCommerce Product Pages

Overview of the issue

After updating WPML, a critical error may occur on some WooCommerce product pages when Elementor and String Translation plugins are active. This issue is triggered by the Elementor integration in WPML when it tries to serialize null data, resulting in a fatal TypeError.

PHP Fatal error: Uncaught TypeError: WPML\PB\Elementor\DataConvert::serialize(): Argument #1 ($data) must be of type array,
null given, called in /wp-content/plugins/sitepress-multilingual-cms/addons/wpml-page-builders/classes/Integrations/Elementor/Hooks/QueryFilter.php on line 34 ...

Workaround

Please, make sure of having a full site backup of your site before proceeding.

• Open the …/wp-content/plugins/sitepress-multilingual-cms/addons/wpml-page-builders/classes/Integrations/Elementor/Hooks/QueryFilter.php file.
• Look for line 28.
• Replace:

  	public function translateQueryIds( $value, $object_id, $meta_key, $single ) {
  		if ( WPML_Elementor_Data_Settings::META_KEY_DATA === $meta_key && $single ) {
  			$value = get_post_meta( $object_id, WPML_Elementor_Data_Settings::META_KEY_DATA, true );
  			if ( $value ) {
  				$value = DataConvert::unserialize( $value, false );
  				$value = $this->recursivelyTranslateQueryIds( $value );
  				$value = DataConvert::serialize( $value, false );
  			}
  		}
  
  		return $value;
  	}
          

• With:

  	public function translateQueryIds( $value, $object_id, $meta_key, $single ) {
  		if ( WPML_Elementor_Data_Settings::META_KEY_DATA === $meta_key && $single ) {
  			$newValue = get_post_meta( $object_id, WPML_Elementor_Data_Settings::META_KEY_DATA, true );
  			if ( $newValue ) {
  				$newValue = DataConvert::unserialize( $newValue, false );
  
  				if ( is_array( $newValue ) ) {
  					$newValue = $this->recursivelyTranslateQueryIds( $newValue );
  					return DataConvert::serialize( $newValue, false );
  				}
  
  				return $value;
  			}
  		}
  
  		return $value;
  	}
          

Our developers are already working on a new release to patch this issue.