Problem

Using supxlabel or supylabel in a constrained layout with auto-positioning and w_pad=0 or h_pad=0 results in labels that have no spacing with respect to the tick labels. Manually changing the position disables the auto-positioning, which makes everything much more difficult.

It would be great if, in that situation, the constrained layout could take axes.labelpad into account and apply that as a minimal padding.

NB: The same might apply to suptitle and titlepad, but I am not sure.

Proposed solution

I think this only requires a change to the make_margin_suptitles() function, but I am not knowledgeable enough to implement such a change.