<h1> Cole o código abaixo em seu arquivo <i> function.php </i> </h1>
//Add Extra Media Type Filters to the WordPress Media Manager
function modify_post_mime_types( $post_mime_types ) {
// select the mime type, here: 'application/pdf'
// then we define an array with the label values
$post_mime_types['application/pdf'] = array( __( 'PDFs' ), __( 'Manage PDFs' ), _n_noop( 'PDF <span class="count">(%s)</span>', 'PDFs <span class="count">(%s)</span>' ) );
// then we return the $post_mime_types variable
return $post_mime_types;
}
// Add Filter Hook
add_filter( 'post_mime_types', 'modify_post_mime_types' );
</code></pre>