Problem

It's sometimes handy to adjust figure height without modifying width. #28758 (comment)

Proposed solution

From #28758 (comment)

Support figure(... ,figsize=...) with tuples where one of x/y can be None with the meaning: Take that component from rcParams["figure.figsize"]; i.e. figsize=(None, 3) is short for figsize=(rcParams["figure.figsize"][0], 3).