node positions do not work with link value zero in Sankey

Hello,
I'm new to the plot.ly lib but I already discovered an issue.
If there is a node with:

• no links
• only links with the value of zero

the manual positioning doesn't work anymore except if you delete the relating coordinates of this node and keep the node in the list (see third example).

Below you can find a short testing code with the generated output.

working example

import plotly.graph_objects as go
data=go.Sankey(
    arrangement = "freeform",
    node = {
        "label": ["A", "B", "C", "D", "E", "F"],
        "x": [0.2, 0.1, 0.9, 0.7, 0.3, 0.9],
        "y": [0.1, 0.9, 0.2, 0.1, 0.9, 0.9],
        'pad':100},  # 10 Pixels 
    link = {
        "source": [0, 0, 1, 4, 4, 3, 3],
        "target": [1, 3, 4, 3, 5, 2, 5],
        "value": [3, 3, 5, 4, 10, 1, 7 ]})
fig_sankey = go.Figure(data=data)
fig_sankey.show()

node with only one link with value of zero

import plotly.graph_objects as go
data=go.Sankey(
    arrangement = "freeform",
    node = {
        "label": ["A", "B", "C", "D", "E", "F"],
        "x": [0.2, 0.1, 0.9, 0.7, 0.3, 0.9],
        "y": [0.1, 0.9, 0.2, 0.1, 0.9, 0.9],
        'pad':100},  # 10 Pixels 
    link = {
        "source": [0, 0, 1, 4, 4, 3, 3],
        "target": [1, 3, 4, 3, 5, 2, 5],
        "value": [3, 3, 5, 4, 10, 0, 7 ]})
fig_sankey = go.Figure(data=data)
fig_sankey.show()

kind of working again cause coordinates of C are deleted

import plotly.graph_objects as go
data=go.Sankey(
    arrangement = "freeform",
    node = {
        "label": ["A", "B", "C", "D", "E", "F"],
        "x": [0.2, 0.1, 0.7, 0.3, 0.9],
        "y": [0.1, 0.9, 0.1, 0.9, 0.9],
        'pad':100},  # 10 Pixels 
    link = {
        "source": [0, 0, 1, 4, 4, 3, 3],
        "target": [1, 3, 4, 3, 5, 2, 5],
        "value": [3, 3, 5, 4, 10, 0, 7 ]})
fig_sankey = go.Figure(data=data)
fig_sankey.show()

首先运行提供的 Python Sankey 示例，并比较其中一个链接的值为零时的自由定位。跟踪 Sankey 的渲染路径，从 Python 图形定义到处理节点位置的组件。完成的标准是：对于没有链接或仅有值为零链接的节点，手动坐标仍然有效，并且有一个覆盖这两种情况的回归测试。