modeBarButtonsToAdd doesn’t appear to be working as intended

Using "modeBarButtonsToAdd" to add buttons for interactive annotations and shape drawing in plotly figures, it prevents the HTML plot to be shown at all with plotly.offline rendering!

import plotly.offline as offline
import plotly.express as px
df = px.data.iris()
fig = px.scatter(df, x='petal_width', y='sepal_length', color='species')
fig.update_layout(
    dragmode='drawopenpath',
    newshape_line_color='cyan',
    title_text='Draw a path to separate versicolor and virginica'
)

config = dict({'scrollZoom': True,'displaylogo': False, 'modeBarButtonsToAdd':['drawline','drawopenpath','drawcircle','drawrect','eraseshape']}) 

offline.plot(fig,  
                     auto_open=True, image = None, config =config, 
                     filename='./foo.html', include_plotlyjs='directory')

If the 'modeBarButtonsToAdd':[ ] is emptied, the HTML is correctly rendered again. Any idea with this weird behaviour?
Please, see also https://eoss-image-processing.github.io/2020/05/06/shape-drawing.html

Environment:
Python 3.7
Plotly 4.14.1
dash 1.18.1

首先使用 plotly.offline.plot 和 modeBarButtonsToAdd 配置运行所提供的 Python 复现代码，并将其与空按钮列表进行比较。跟踪离线 HTML 的生成过程，并验证在启用绘图按钮时输出能够成功渲染；检查行为时使用所报告的 Python 3.7 和 Plotly 4.14.1 环境。