anchor.diff:                  textView.TextSnapshot.GetLineNumberFromPosition(pos))
               |> Seq.distinct
               |> Seq.iter (fun lineNo ->                
  -                    let markerHeight = textView.LineHeight / 3.0
  -                    let markerWidth = 20.0
  +                    let markerHeight = min 4.0 (lineHeight / 2.0)
  +                    let markerWidth = verticalScrollBar.MarginSize
                       let marker = Rectangle(Fill = Brushes.Orange, StrokeThickness = 2.0, Stroke = Brushes.DarkOrange,
                                              Height = markerHeight, Width = markerWidth)
                       Canvas.SetLeft(marker, -markerWidth)
  -                    Canvas.SetTop(marker, float lineNo * textView.LineHeight)
  +                    Canvas.SetTop(marker, float lineNo * lineHeight)
                       marker.MouseDown.Add(fun _ -> 
                           let line = textView.TextSnapshot.GetLineFromLineNumber(lineNo)
                           textView.ViewScroller.EnsureSpanVisible(SnapshotSpan(line.Start, 0), EnsureSpanVisibleOptions.AlwaysCenter))
  
positive.code: open Microsoft.VisualStudio.Text.Tagging
  
  [<Name("UnusedDeclarationMargin")>]
  type UnusedDeclarationMargin(textView: IWpfTextView, tagAggregator: ITagAggregator<UnusedDeclarationTag>) =
      inherit Canvas()
  
      let children = base.Children
  
      let updateDisplay () =
           if not textView.IsClosed then
              children.Clear()
              let span = SnapshotSpan(textView.TextBuffer.CurrentSnapshot, 0, textView.TextBuffer.CurrentSnapshot.Length)
              tagAggregator.GetTags(span)
              |> Seq.map (fun span -> 
  
negative.code:     [<Import>]
      member val TagAggregatorFactoryService: IViewTagAggregatorFactoryService = null with get, set
      interface IWpfTextViewMarginProvider with
          member x.CreateMargin(wpfTextViewHost: IWpfTextViewHost, marginContainer: IWpfTextViewMargin): IWpfTextViewMargin = 
              let textView = wpfTextViewHost.TextView
              new UnusedDeclarationMargin(textView, marginContainer,
                      x.TagAggregatorFactoryService.CreateTagAggregator<UnusedDeclarationTag>(textView)) :> _
          
          
  
  