markoheijnen / tabify-edit-screen

		$metaboxes         = array();

		$default_metaboxes = $this->get_default_items( $post_type );

		foreach ( $wp_meta_boxes[ $post_type ] as $priorities ) {

			foreach ( $priorities as $priority => $_metaboxes ) {

				foreach ( $_metaboxes as $metabox ) {

					if ( ! in_array( $metabox['id'], $default_metaboxes ) ) {

						$metaboxes[ $metabox['id'] ] = $metabox['id'];

					}

				}

			}

		}

		return $metaboxes;

	}

			do_action( 'tabify_add_meta_boxes', $posttype );

		}

		foreach ( $wp_meta_boxes as $posttype => $context ) {

			foreach ( $context as $priorities ) {

				foreach ( $priorities as $priority => $_metaboxes ) {

					foreach ( $_metaboxes as $metabox ) {

						// Metabox has been removed

						if ( ! isset( $metabox['id'] ) ) {

							continue;

						}

						$metaboxes[ $posttype ][ $metabox['id'] ] = $metabox['title'];

					}

				}

			}

		}

		return $metaboxes;