Hide empty categories in menus

functions.php

//Hide empty categories in menus
add_filter( 'wp_get_nav_menu_items', 'nav_remove_empty_category_menu_item',10, 3 );
function nav_remove_empty_category_menu_item ( $items, $menu, $args ) {
    if ( ! is_admin() ) { 
        global $wpdb;
        $nopost = $wpdb->get_col( "SELECT term_taxonomy_id FROM $wpdb->term_taxonomy WHERE count = 0" );
        foreach ( $items as $key => $item ) {
            if ( ( 'taxonomy' == $item->type ) && ( in_array( $item->object_id, $nopost ) ) ) {
                unset( $items[$key] );
            }
        }
    }
    return $items;
}