Ticket #19856: 19856-2.patch

wp-includes/functions.php

@@ -1261 +1261 @@
         else if ( ! empty( $_SERVER['HTTP_REFERER'] ) )
                 $ref = $_SERVER['HTTP_REFERER'];
 
-        if ( $ref && $ref !== $_SERVER['REQUEST_URI'] )
+        if ( $ref && $ref !== get_site_url() . $_SERVER['REQUEST_URI'] )
                 return $ref;
         return false;
 }