[BUG]: FigureWidget: layout.shapes not updated after drawing a path in JupyterLab

[eugenekwaNeuromics]

Description

When attempting to enable draw closed paths on a plotly.graph_objects.FigureWidget, I noticed that there was an issue when attempting to delete the existing drawn paths. It seems that while fig.layout.to_plotly_json().get("shapes") is able to detect the path drawn, this information is not relayed to fig.layout.shapes. This can be fixed by manually editing fig.layout.to_plotly_json().get("shapes"), plugging it into fig.layout.shapes, and then deleting. The manual edits are to remove the <object object at 0x000001BFE6411440> that is assigned to both "name" and "legendwidth".

Steps to reproduce

import plotly.graph_objects as go
import ipywidgets as widgets
from IPython.display import display

fig = go.FigureWidget(
    go.Heatmap(
        z=[[1, 2], [3, 4]],
        showscale=False,
    )
)

fig.update_layout(
    dragmode="drawclosedpath",
    newshape=dict(
        line=dict(color="red", width=2)
    )
)

fail_clear_button = widgets.Button(description="Clear ROI (Fails)")
working_clear_button = widgets.Button(description="Clear ROI (Works)")
out = widgets.Output() 

def clear_roi(_):
    with out:
        print("layout.shapes:", fig.layout.shapes)
        print("JSON shapes:", fig.layout.to_plotly_json().get("shapes"))
        with fig.batch_update():         
            fig.layout.shapes = []
        print("After update_layout")
        print("layout.shapes:", fig.layout.shapes)
        print("JSON shapes:", fig.layout.to_plotly_json().get("shapes"))

def clear_roi_alt(_):
    with out:
        print("layout.shapes:", fig.layout.shapes)
        print("JSON shapes:", fig.layout.to_plotly_json().get("shapes"))
        json_shapes = fig.layout.to_plotly_json().get("shapes", [])
        for s in json_shapes:
            s['legendwidth'] = 0
            s['name'] =  ''
        fig.layout.shapes = json_shapes
        print("After pulling from JSON")
        print("layout.shapes:", fig.layout.shapes)
        print("JSON shapes:", fig.layout.to_plotly_json().get("shapes"))
        fig.layout.shapes = []
        print("After clearing")
        print("layout.shapes:", fig.layout.shapes)
        print("JSON shapes:", fig.layout.to_plotly_json().get("shapes"))

fail_clear_button.on_click(clear_roi)
working_clear_button.on_click(clear_roi_alt)

display(widgets.VBox([fail_clear_button, working_clear_button, fig, out]))

Notes

Python: 3.12.13
Plotly: 6.9.0
JupyterLab: 4.5.6
ipywidgets: 8.1.8
OS: Windows-11-10.0.26100-SP0