Chapter 23 WAN Optimization, Web Cache, Explicit Proxy, and WCCP : The FortiGate explicit web proxy : Explicit web proxy firewall address URL patterns : URL patterns and HTTPS scanning
  
URL patterns and HTTPS scanning
For HTTPS traffic, URL patterns can only be matched up to the root path. For example, consider the following URL pattern:
www.apple.com/ipad/
If a proxy user browses using HTTP, this URL pattern limits their access the iPad pages of www.apple.com. However, if a proxy user browses using HTTPS, they will be able to access all pages on www.apple.com.