Bug summary

Although the documentation says that all Line2D kwargs should be supported, only a small handful actually are:

markerfacecoloralt is not among that list.

Code for reproduction

import numpy as np
import matplotlib.pyplot as plt

# example data
x = np.arange(0.1, 4, 0.5)
y = np.exp(-x)

# example error bar values that vary with x-position
error = 0.1 + 0.2 * x

fig, ax = plt.subplots(1, 1)
ax.errorbar(x, y, yerr=error, fmt='-o', markerfacecoloralt='white')
ax.set_title('variable, symmetric error')

Actual outcome

AttributeError: 'LineCollection' object has no property 'markerfacecoloralt'

Expected outcome

No error

Additional information

markerfacecoloralt needs to be added to this list:

Better yet, automagically check against the signature of Line2D.

Operating system

Ubuntu 20.04.4

Matplotlib Version

3.5.2

Matplotlib Backend

QtAgg

Python version

3.8.10

Jupyter version

No response

Installation

pip