Chapter 1 What’s New for FortiOS 5.2.1 : Top Features : Web Filtering
  
Web Filtering
Several new options have been added for web filtering:
Restricting Google access to specific domains
New protocols for warnings and authentication
Modifying HTTP request headers
Adding a referer to URL filters.
Using FortiGuard rating checks for images, JavaScript, CSS, and CRL
Additional replacement message variables
For more information, see “Web Filtering”.