On the commit 2048bec it looks like you have changed the number of args required for the function _add_leaf_error_subplot( ) from 3 to 2, by removing "fig". def _add_leaf_error_subplot(self, ax, fig): ...
Trying to combine subplot_mosaic with axes using various different projections (e.g. one rectilinear axes and one polar axes and one 3d axes) has been requested a few times (once in the original ...