Visual bug for nodes with fixed position in Sankey plot

There seems to be a visual bug for nodes with fixed positions that makes it hard to differentiate between incomming and outgoing links.
It would be great if this would be solves the same way it is solved with loops. In my example the left side that has no loop therefore would likely be read as a link from node B to A. The right side however has a loop and solves the issue by implementing a visual that shows clearly that the link from node D to C is outgoing at D terefore on the right side and incomming at C therefore on the left side.

  fig = go.Figure(data=[go.Sankey(
      arrangement="snap",
      node=dict(
          label=["A", "B", "C", "D", "E", "F", "G", "H"],
          x=[0.3, 0.4, 0.6, 0.7],
          y=[0.5, 0.5, 0.5, 0.5]
      ),
      link=dict(
          source=[1, 2, 3],
          target=[0, 3, 2],
          value=[1, 1, 1]
      ))])
  fig.show()

Comienza ejecutando la reproducción de Sankey en Python proporcionada y compara los enlaces con posición fija con el renderizado de bucle mostrado en el ejemplo. Rastrea el punto de entrada del renderizado de Sankey y determina cómo se comunica la dirección de los enlaces en cada nodo; se considera terminado cuando los enlaces entrantes y salientes se distinguen visualmente en el diseño indicado sin introducir regresiones en el renderizado de bucles.