textfont color ignored in Sankey diagram

When specifying textfont in a Sankey diagram like this: textfont=dict(color="blue", size=50) the color is ignored, while size works correctly.

A MWE with two figures. The first one has black nodes and (tiny) text, which is correct.

fig_black = go.Figure(data=[
    go.Sankey(
        node=dict(
            pad=15,
            thickness=20,
            line=dict(color="black", width=0.5),
            label=["A1", "A2", "B1", "B2", "C1", "C2"],
            color="black"
        ),
        link=dict(
            source=[0, 1, 0, 2, 3, 3],  # indices correspond to labels, eg A1, A2, A2, B1, ...
            target=[2, 3, 3, 4, 4, 5],
            value=[8, 4, 2, 8, 4, 2]
        ),
        textfont=dict(color="black", size=10)
    ),
])
fig_black.update_layout(title_text="Black")
fig_black.show()

The second one has blue nodes, which is correct, but the text is black when it should be blue.

fig_blue = go.Figure(data=[
    go.Sankey(
        node=dict(
            pad=15,
            thickness=20,
            line=dict(color="blue", width=0.5),
            label=["A1", "A2", "B1", "B2", "C1", "C2"],
            color="blue"
        ),
        link=dict(
            source=[0, 1, 0, 2, 3, 3],  # indices correspond to labels, eg A1, A2, A2, B1, ...
            target=[2, 3, 3, 4, 4, 5],
            value=[8, 4, 2, 8, 4, 2]
        ),
        textfont=dict(color="blue", size=50)
    ),
])
fig_blue.update_layout(title_text="Blue")
fig_blue.show()

I'm using plotly version 4.9.0.

Is the color specification above wrong or is this a bug?

Reproduziere das bereitgestellte Sankey-MWE mit zwei Abbildungen mit Plotly 4.9.0 und vergleiche die funktionierende Textgröße mit der ignorierten Textfarbe. Verfolge die Verarbeitung von Sankey textfont und füge eine Abdeckung hinzu, die zeigt, dass die angeforderte Farbe gerendert wird; das Issue nennt zunächst keine Quelldatei und keinen Test.