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filter is not described

custom_menu_order filter-hook . WP 2.8.0

Filters whether to enable custom ordering of the administration menu.

See the 'menu_order' filter for reordering menu items.

Usage

add_filter( 'custom_menu_order', 'filter_function_name_2844' );
function filter_function_name_2844( $custom ){
	// filter...

	return $custom;
}
$custom(true/false)
Whether custom ordering is enabled.
Default: false

Where the hook is called

In file: /wp-admin/includes/menu.php
custom_menu_order
wp-admin/includes/menu.php 252
if ( apply_filters( 'custom_menu_order', false ) ) {

Where the hook is used (in WP core)

wp-admin/includes/menu.php 266
* add_filter( 'custom_menu_order', '__return_true' );