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function is not described

_wp_nav_menu_meta_box_object() WP 3.0.0

Adds custom arguments to some of the meta box object types.

This is an internal function for using it by WP core itself. It's not recommended to use this function in your code.

No Hooks.

Return

Object. The post type or taxonomy object.

Usage

_wp_nav_menu_meta_box_object( $object );
$object(object)
The post type or taxonomy meta-object.
Default: null

Changelog

Since 3.0.0 Introduced.

Code of _wp_nav_menu_meta_box_object() WP 5.8.2

function _wp_nav_menu_meta_box_object( $object = null ) {
	if ( isset( $object->name ) ) {

		if ( 'page' === $object->name ) {
			$object->_default_query = array(
				'orderby'     => 'menu_order title',
				'post_status' => 'publish',
			);

			// Posts should show only published items.
		} elseif ( 'post' === $object->name ) {
			$object->_default_query = array(
				'post_status' => 'publish',
			);

			// Categories should be in reverse chronological order.
		} elseif ( 'category' === $object->name ) {
			$object->_default_query = array(
				'orderby' => 'id',
				'order'   => 'DESC',
			);

			// Custom post types should show only published items.
		} else {
			$object->_default_query = array(
				'post_status' => 'publish',
			);
		}
	}

	return $object;
}