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()

Start by running the provided Python Sankey reproduction and compare fixed-position links with the loop rendering shown in the example. Trace the Sankey rendering entry point and determine how link direction is communicated at each node; done means incoming and outgoing links are visually distinguishable in the reported layout without regressing loop rendering.