The way this counter works is that it contains the SessionPageNumber of the page owner and a fraction containing the sequence number of page served to the root page owning the request. This allows for an efficient way to locate the root as well as sort all dependent requests.
On a a Web page with user discovery enabled you would get:
1. [The Page].0
2. [The Page].IsUserJavaStript
3. [The Page].SiteMap
4. [The Page].UserDiscovery
N.[The Page].UserDiscovery multiple / optional
N.[The Page].Beacon Optional
Not having this pattern is picked up by the virus engine as replay or a user using developer tools as loading the same user script or resource multiple times without the root page is a indicator non-default browser activity (based on user agent key) has been detected.
Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2