I am looking into the possibilities of
\pgfdeclarefunctionalshading for the first time. I found this post on TeX.se and tried pasting its MWE into my LaTeX editor (MacTeX 2020, up to date, run through VSCode's LaTeX Workshop) to play around with. However, instead of getting several shaded bands, I got a bunch of pink bands.
I thought it might be something local, but I got an identical result when I tried the MWE in Overleaf. Now the linked post is five years old, so I was wondering if
\pgfdeclarefunctionalshading is being phased out or is broken right now (i.e., there's a bug)... But I really have no idea what's going on.
Any thoughts? If there's anything else I can provide, let me know!