Plotnine Warning: Failed to apply `after_scale` modifications to the legend

[vale46]

Hello -

Trying to do a plot similar to https://plotnine.org/gallery/violins-boxes-points-and-lines.html. However, in my data, I'd like use a continuous variable as a size aesthetic in geom_point. Here's a MWE with a slightly modified dataset:

import plotnine a p9
import numpy as np
import pandas as pd

np.random.seed(123)
n = 20
mu = (1, 2.3)
sigma = (1, 1.6)

before = np.random.normal(loc=mu[0], scale=sigma[0], size=n)
after = np.random.normal(loc=mu[1], scale=sigma[1], size=n)
size = np.random.uniform(10, 20, 2*n)

df = pd.DataFrame(
    {
        "value": np.hstack([before, after]),
        "when": np.repeat(["before", "after"], n),
        "point_size": np.hstack([size]),
    }
)

lsize = 0.65
fill_alpha = 0.7
m1 = p9.aes(x=p9.stage("when", after_scale="x+shift*alt_sign(x)"))  # shift outward
m2 = p9.aes(x=p9.stage("when", after_scale="x-shift*alt_sign(x)"), size='point_size') # shift inward

plot = (
    p9.ggplot(df, p9.aes("when", "value", fill="when"))
    + p9.geom_violin(m1, style="left-right", alpha=fill_alpha, size=lsize)
    + p9.geom_boxplot(width=shift, alpha=fill_alpha, size=lsize)
    + p9.geom_point(m2, color="none", alpha=fill_alpha)
    + p9.scale_fill_manual(values=["dodgerblue", "darkorange"])
    + p9.guides(fill=False)  # Turn off the fill legend
    + p9.theme_classic()
    + p9.theme(figure_size=(8, 6))
)

plot.show()

This produces the following warning message:
guide_legend.py:183: PlotnineWarning: Failed to apply after_scale modifications to the legend.

with an incomplete legend that's missing the circle in each of the legend entries (see attached image).

Legend entries should not be impacted by the after_scale adjustment on this plot.

Greatly appreciate further thoughts.
Thanks