go.Contour doesn't render correctly in animation frames when multiple traces are present

I'm encountering an issue with plotly.graph_objects.Figure animations. When using go.Contour inside go.Frame along with additional traces such as go.Scatter, the contour plot no longer renders correctly during animation. However, if I only include the go.Contour trace by itself in each frame, it animates perfectly.
Here's a minimal reproducible example:

import plotly.io as pio
pio.renderers.default = 'browser'
import plotly.graph_objects as go
import numpy as np

z_base = np.array([
    [10, 10.625, 12.5, 15.625, 20],
    [5.625, 6.25, 8.125, 11.25, 15.625],
    [2.5, 3.125, 5., 8.125, 12.5],
    [0.625, 1.25, 3.125, 6.25, 10.625],
    [0, 0.625, 2.5, 5.625, 10]
])

lk_x=[0,0,1,1,0]
lk_y=[0,1,1,0,0]

data_line = go.Scatter(x=lk_x, y=lk_y, mode='lines', fill='toself', fillcolor='rgba(60, 53, 48, 0.5)', line_color='black', showlegend=False)

scales = np.linspace(0.2, 1.0, 10)
frames = []
for i, s in enumerate(scales):
    z_scaled = z_base * s
    frames.append(go.Frame(
        data=[
            go.Contour(
                z=z_scaled,
                colorbar=dict(
                    thickness=25,
                    thicknessmode='pixels',
                    len=0.6,
                    lenmode='fraction',
                    outlinewidth=0
                )
                ,zorder=2
            ),
            go.Scatter(
                x=[0, 1, 2, 3, 4],
                y=[0, 1, 1.5, 2, 3], 
                mode='lines',
                line=dict(color='black', width=2),
                showlegend=False,
                zorder=0
            ),
            data_line
        ],
        name=f"scale_{i}"
    ))


fig = go.Figure(
    data=frames[0].data,
    frames=frames
)

fig.update_layout(
    title="Contour",
    updatemenus=[{
        "buttons": [
            {"label": "play", "method": "animate", "args": [None, {"frame": {"duration": 500}, "fromcurrent": True}]},
            {"label": "pause", "method": "animate", "args": [[None], {"mode": "immediate", "frame": {"duration": 0}}]}
        ],
        "type": "buttons",
        "showactive": True,
        "x": 0.1,
        "y": -0.1
    }],
    sliders=[{
        "steps": [{"args": [[f.name]], "label": f"Step {i+1}", "method": "animate"} for i, f in enumerate(frames)],
        "x": 0.1,
        "len": 0.9
    }],
    width=500,
    height=500
)

fig.show()

only include the go.Contour trace：

with additional traces：

Commencez par exécuter l’exemple minimal Python fourni dans plotly.py et comparez l’animation utilisant uniquement go.Contour avec l’animation incluant les traces go.Scatter supplémentaires. Suivez le chemin d’animation/rendu utilisé par Figure et Frame pour les données de contour ; le travail est terminé lorsque le contour est correctement rendu tout au long des frames lorsque plusieurs traces sont présentes, sans régression dans le cas d’une seule trace.