DepreciationWarning in toolbar causes AttributeError

[raphaelquast]

Describe the issue

Accessing toolbar properties causes AttributeError: 'super' object has no attribute '__getattr__'

The problematic lines are here:

ipympl/ipympl/backend_nbagg.py

Lines 162 to 170 in 238d796

	def __getattr__(self, name):
	if name in ['orientation', 'collapsed']:
	warn(
	"The Toolbar properties 'orientation' and 'collapsed' are deprecated."
	"Accessing them will raise an error in a coming ipympl release",
	DeprecationWarning,
	)
	return super().__getattr__(name)

This is most probably caused by the mixin-style classes ... a explanation (and a possible solution) might be this:

https://stackoverflow.com/a/28864246/9703451

Versions

 3.11.3 | packaged by conda-forge | (main, Apr  6 2023, 08:50:54) [MSC v.1934 64 bit (AMD64)]
ipympl version: 0.9.3