.NET Standard UWP PlatformNotSupported exception

Hi,

I just moved my project to .NET standard as instructed here.

After fixing all libs, when running the UWP, I get the following exception:

System.PlatformNotSupportedException: 'Arg_PlatformNotSupported'

As you can see in the following image, there is no StackTrace, but FWIW, I included the stack frame list.