Rocket Validator integrates the W3C Validator HTML checker into an automated web crawler.
HTML issues tagged as data attributes.
The <span> element does not have a currency attribute. Consider using custom data attributes instead, like data-currency.
The attribute st_title is not allowed on <span> elements.
This issue is commonly caused by an old integration of ShareThis via Drupal or other CMS - the old code used invalid attributes like displayText, st_url and st_title which were later changed to HTML5 custom data attributes.
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