Matplotlib 3.8 fails to plot irregular meshes

[guyer]

As documented in Matplotlib "API Changes for 3.8.0",

FIPY_VIEWER=matplotlib python examples/diffusion/circle.py

raises

ImportError: Failed to import a viewer: ['matplotlib: Unable to determine Axes to steal space for Colorbar. Either provide the *cax* argument to use as the Axes for the Colorbar, provide the *ax* argument to steal space from it, or add *mappable* to an Axes.']

Matplotlib 3.7 is fine. Regular meshes are fine.

Discussed in #1006

^{Originally posted by agoncalvescoel February 9, 2024}
Hey guys,

I'm learning how to use this amazing tool, and while I was going through the manual, I had some errors running some scripts from the examples folder: coupled.py, and circle.py.

It gives me extensive lists of errors and the program crashes. Here's a print of the first ones:

When writing coupled one myself I did notice that I only had errors when trying the vector form.
Anyone can help me with what I am doing wrong here?

[guyer]

Hmm... regular meshes are not OK, either. They just freeze after updating macOS from 13.6(?) to 14.3.1.

[guyer]

The freeze is reported in matplotlib/matplotlib#27720 and reportedly fixed in matplotlib/matplotlib#27755.

Issue still present in mpl 3.8.3