突出显示在Wordpress中返回访问者的新帖子

I am working on highlighting new content in wordpress multisite so that I attract visitor's attention to the latest content. To achieve this. In your functions.php you need to add:

function wpb_lastvisit_the_title ( $title, $id ) {

if ( !in_the_loop() || is_singular() || get_post_type( $id ) == 'page' ) return $title;

// if no cookie then just return the title 

if ( !isset($_COOKIE['lastvisit']) ||  $_COOKIE['lastvisit'] == '' ) return $title;
$lastvisit = $_COOKIE['lastvisit'];
$publish_date = get_post_time( 'U', true, $id );
if ($publish_date > $lastvisit) $title .= '<span class="new-article">New</span>';
return $title;

}

add_filter( 'the_title', 'wpb_lastvisit_the_title', 10, 2);

// Set the lastvisit cookie 

function wpb_lastvisit_set_cookie() {

if ( is_admin() ) return;
$current = current_time( 'timestamp', 1);
setcookie( 'lastvisit', $current, time()+60+60*24*7, COOKIEPATH, COOKIE_DOMAIN );
}

add_action( 'init', 'wpb_lastvisit_set_cookie' );

In your CSS, you need to add:

.new-article { 
background: #feffdd;
padding: 3px;
border: 1px solid #eeefd2;
-webkit-border-radius: 5px;
-moz-border-radius: 5px;
border-radius: 5px;
margin-left:5px;
font-size: small;
font-weight: bold;
}

This only works on wordpress single site install, it does not work on wordpress multisite. Do I have anything missing? I need this work on wordpress multisite.

Thanks