If you are getting the “URI malformed” error in the browser console when trying to use the WPBakery Page Builder Front-End editor it is most likely an issue with the Database Charset used on the site. If you are having this error you may also be seeing strange characters on the front-end.
To fix you can contact your webhost and they should fix it for you or you can try editing your wp-config.php file and making sure the DB_CHARSET definition is correct.
