Ticket #34450: 34450.patch

src/wp-includes/ms-blogs.php

@@ -84 +84 @@
                 return $blog_id;
 
         if ( is_subdomain_install() ) {
-                $domain = $slug . '.' . $current_site->domain;
+                $domain = $slug . '.' . preg_replace( '|^www\.|', '', $current_site->domain );
                 $path = $current_site->path;
         } else {
                 $domain = $current_site->domain;