Horizontal zooming on faceted scatter plots does not scale y axes correctly

[mcenno]

The code below produces two plots side by side. Zooming in on the x axis only, using a horizontal motion of the mouse, results in the two y axes being independently rescaled. Zooming using a rectangle or on the y axis works as expected. The error does not appear when using fewer than 501 points.

I'm using Python 3.7.4 and Plotly 4.9.0 on Windows 10.

Example:

import plotly.express as px
import numpy as np
import pandas as pd
size=501
df = pd.DataFrame({'x': np.random.random(size=2*size),
                   'y': np.hstack((np.random.normal(loc=10,  scale=2, size=size), 
                                   np.random.normal(loc=100, scale=2, size=size))),
                   'c': np.hstack((np.zeros(shape=size), np.ones(shape=size)))})

fig = px.scatter(data_frame=df, x='x', y='y', facet_col='c')
fig.show()