WordPress + HTML Validation

Using W3C Markup Validation Service.

remove type attribute from script tag

Warning: The type attribute is unnecessary for JavaScript resources.

add_filter('style_loader_tag', 'themename_remove_type_attr_from_script', 10, 2);
add_filter('script_loader_tag', 'themename_remove_type_attr_from_script', 10, 2);

function themename_remove_type_attr_from_script($tag, $handle) {
    return preg_replace( "/type=['\"]text\/(javascript|css)['\"]/", '', $tag );
}