System.TypeLoadException: 'Could not resolve type with token 01000019 from typeref (expected class 'Xamarin.Forms.Xaml.Diagnostics.VisualDiagnostics' in assembly 'Xamarin.Forms.Core, Version=2.0.0.0, Culture=neutral, PublicKeyToken=null')' code example
Example: Could not resolve type with token 01000013 from typeref
Update all packages and delete bin and obj folders, clean and rebuild