anchor.diff:  
   
   /// Plotly color can be a single color, a sequence of colors, or a sequence of numeric values referencing the color of the colorscale obj
  +[<JsonConverter(typeof<ColorConverter>)>]
   type Color private(obj:obj) =
   
       /// Creates a Color from the four ARGB component (alpha, red, green, and blue) values.
       static member fromArgb a r g b =
  -        RGB.create a r g b 
  +        RGB.create a r g b
  +        |> unbox
  +        |> Color
           // let fi v =
           //     if v < 0 || v > 255 then 
           //         failwithf "Value for component needs to be between 0 and 255."
  
positive.code:     /// Creates a Color from the specified color values (red, green, and blue).
      /// The alpha value is implicitly 1. (fully opaque). 
      static member fromRgb r g b =
          Color.fromArgb 256 r g b
  
      /// Color from hex representataion (FFFFFF) or (0xFFFFFF)
      static member fromHex (s:string) =
  
negative.code:         override _.WriteJson(writer, value, serializer) =       
              let argb = value :?> Argb
              //writer.WriteValue(sprintf "rgba(%i, %i, %i, %0.1f)" argb.R argb.G argb.B argb.A )
              writer.WriteValue(sprintf "rgba(%i, %i, %i, %0.1f)" argb.R argb.G argb.B (float argb.A / 255.))
  
      /// Creates a Argb Color from the four ARGB component (alpha, red, green, and blue) values.
      let create a r g b =
  