Remove border on custom meta box

Question

How can i remove the border/box on a custom meta box?

I need to remove the class "postbox" from a custom meta box, so that it looks just plain.

How can i do that?

Answer 1

The postbox class is hardcoded into the do_meta_boxes() function which is responsible for rendering meta boxes, and is not customizable via filters. Thus, I guess your best bet would be removing it using javascript. This should do it:

functions.php

add_action('admin_init', 'wpse_87339_admin_init');
function wpse_87339_admin_init() {
    wp_enqueue_script('wpse_87339_admin', get_stylesheet_directory_uri() . '/js/admin.js', array('jquery'));
}

js/admin.js

jQuery(document).ready(function($) {
    // Remove all .postbox classes from sidebar
    $('#side-sortables .postbox').removeClass('postbox');

    // Remove .postbox from specific metabox (page attributes)
    $('#pageparentdiv').removeClass('postbox');
});