`groupclick="toggleitem"` Does Not Work Consistently Across Subplots in Plotly

Description

When using the groupclick="toggleitem" parameter in Plotly with subplots, the toggling behavior for legend items only applies to traces in the first subplot. Traces in other subplots are not affected as expected, even when the legendgroup attribute is set consistently for all relevant traces.

This issue breaks the intended behavior of groupclick="toggleitem" for figures with subplots, where users would expect the toggling of a legend item to apply uniformly across all traces in the same legendgroup, regardless of their subplot.

Expected Behavior

Clicking a legend item with groupclick="toggleitem" should toggle the visibility of all traces in the corresponding legendgroup, including traces in subplots other than the first.

Observed Behavior

When clicking a legend item:

• The visibility of traces is toggled only in the first subplot.

• Traces in other subplots within the same legendgroup remain unaffected.

Minimal Reproducible Example

import plotly.graph_objects as go
from plotly.subplots import make_subplots

# Create a subplot figure
fig = make_subplots(rows=3, cols=1)

# Add traces to the first subplot
fig.add_trace(go.Scatter(x=[1, 2, 3], y=[1, 4, 9], name="Group A", legendgroup="group_a"), row=1, col=1)
fig.add_trace(go.Scatter(x=[1, 2, 3], y=[2, 4, 8], name="Group B", legendgroup="group_b"), row=1, col=1)

# Add traces to the second subplot
fig.add_trace(go.Scatter(x=[1, 2, 3], y=[1, 3, 6], name="Group A", legendgroup="group_a", showlegend=False), row=2, col=1)
fig.add_trace(go.Scatter(x=[1, 2, 3], y=[2, 5, 7], name="Group B", legendgroup="group_b", showlegend=False), row=2, col=1)

# Add traces to the third subplot
fig.add_trace(go.Scatter(x=[1, 2, 3], y=[1, 2, 3], name="Group A", legendgroup="group_a", showlegend=False), row=3, col=1)
fig.add_trace(go.Scatter(x=[1, 2, 3], y=[3, 5, 9], name="Group B", legendgroup="group_b", showlegend=False), row=3, col=1)

# Update layout with groupclick parameter
fig.update_layout(
    legend=dict(groupclick="toggleitem")
)

fig.show()

Steps to Reproduce

1. Run the provided example code.

2. Click on a legend item for "Group A" or "Group B."

3. Observe that the traces in the first subplot toggle visibility as expected.

4. Notice that traces in other subplots do not toggle visibility.

### Environment

Plotly Version: 5.24.1
Python Version: 3.11.9
Operating System: Windows 11
Browser: Edge 131.0.2903.86

Additional Notes

The issue does not occur when the groupclick parameter is omitted. The default behavior works as expected, where clicking a legend item toggles all traces in the same legendgroup across all subplots.

However, groupclick="toggleitem" is necessary for more granular control of legend interactions, and it should work consistently across subplots.

Inizia eseguendo l’esempio minimo riproducibile in Python fornito con Plotly 5.24.1 e verifica il comportamento della legenda in tutti e tre i subplot. Traccia il punto di ingresso dell’interazione con la legenda nel repository o nella relativa integrazione di Plotly.js, quindi aggiungi la copertura per groupclick="toggleitem" con gruppi di legenda condivisi. Il lavoro è completato quando facendo clic su un elemento della legenda si applica in modo coerente la modifica di visibilità prevista in ogni subplot.