Bug: leftover xaxis entries when toggling between buttons

[arnaudh]

Minimum Working Example (MWE):

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

# Data
option1_x = ['A', 'B', 'C']
option1_y1 = [1, 3, 2]
option1_y2 = [2, 4, 3]

option2_x = ['B', 'D', 'E']
option2_y1 = [2, 1, 4]
option2_y2 = [3, 2, 5]

# Create subplots
fig = make_subplots(rows=2, cols=1, shared_xaxes=True, subplot_titles=("y1", "y2"))

# Add traces for option1
fig.add_trace(go.Bar(x=option1_x, y=option1_y1, name="option1_y1"), row=1, col=1)
fig.add_trace(go.Bar(x=option1_x, y=option1_y2, name="option1_y2"), row=2, col=1)

# Add traces for option2
fig.add_trace(go.Bar(x=option2_x, y=option2_y1, name="option2_y1"), row=1, col=1)
fig.add_trace(go.Bar(x=option2_x, y=option2_y2, name="option2_y2"), row=2, col=1)

# Initially set option1 visible and option2 invisible
for trace in fig.data:
    trace.visible = False
fig.data[0].visible = True  # y1 option1
fig.data[1].visible = True  # y2 option1

# Add buttons
fig.update_layout(
    updatemenus=[
        {
            "type": "buttons",
            "buttons": [
                {
                    "label": "option1",
                    "method": "update",
                    "args": [
                        {"visible": [True, True, False, False]},  # Show only option1 traces
                    ]
                },
                {
                    "label": "option2",
                    "method": "update",
                    "args": [
                        {"visible": [False, False, True, True]},  # Show only option2 traces
                    ]
                }
            ],
            "showactive": True,
        }
    ],
)

fig.show()

Toggling to option2, we can see the C xaxis entry (from option1) still showing (even with no data for it):

This seems to only be an issue with subplots, and when the traces of different options have some xaxis labels in common (in this case B).

[arnaudh]

One workaround I found is to reset axes by passing "xaxis": {} (and "xaxis2": {}) as second args to buttons, i.e.:

fig.update_layout(
    updatemenus=[
        {
            "type": "buttons",
            "buttons": [
                {
                    "label": "option1",
                    "method": "update",
                    "args": [
                        {"visible": [True, True, False, False]},  # Show only option1 traces
                        {
                            "xaxis": {},
                            "xaxis2": {},
                        },
                    ]
                },
                {
                    "label": "option2",
                    "method": "update",
                    "args": [
                        {"visible": [False, False, True, True]},  # Show only option2 traces
                        {
                            "xaxis": {},
                            "xaxis2": {},
                        },
                    ]
                }
            ],
            "showactive": True,
        }
    ],
)