WPF Create Visual with border that appears to be only inside of drawn geometry

WPF Visual Geometry Border Inside

private static DrawingVisual CreateVisual()
        {
            var noBorderPen = new Pen(new SolidColorBrush(Colors.Transparent), 0);
            var selectionPen = new Pen(new SolidColorBrush(Colors.Yellow), 20 * 2);
            var drawingVisual = new DrawingVisual();

            using (var dc = drawingVisual.RenderOpen())
            {
                StreamGeometry geometry = new StreamGeometry();

                using (var ctx = geometry.Open())
                {
                    ctx.BeginFigure(new Point(100, 100), true, true);
                    ctx.LineTo(new Point(300, 100), true, false);
                    ctx.LineTo(new Point(300, 200), true, false);
                }

                // Draw the geometry
                dc.DrawGeometry(new SolidColorBrush(Colors.Fuchsia), noBorderPen, geometry);
                
                // Apply a clip path to only draw the geometry and hide everything outside
                dc.PushClip(geometry);

                // Draw the geometry on top with the selection border
                dc.DrawGeometry(Brushes.Transparent, selectionPen, geometry);

                // Remove the clip path
                dc.Pop();

                geometry.Freeze();
            }

            return drawingVisual;
        }