Issue
You see certain third-party libraries marked as Unknown or gray in Contrast.
Cause
Contrast uses a database of library file hashes to identify libraries. This library database is based on information from the Nuget package repository (the de facto standard repository for .NET libraries). Most popular third-party libraries such as Entity Framework are published on Nuget. However, Contrast doesn't identify the libraries that aren't published in the repository, including most first-party Microsoft libraries such as System.Data or System.Web (but not System.Mvc). Contrast may identify more first-party libraries in future versions.
Resolution
There is no action to take at this time.