It seems the newest version of ShaderGraph, part of Unity URP, with date 10/24/2022, installed with 2022.1.21f1 has two missing symbols that prevent its compilation. Things like “reimport all” to rebuild the library didn’t help. Some materials using shadergraph will come out with that “error pink/magenta” look.
I re-downgraded my RPG project to 2022.1.20, and it appeared to work all right (so far). But I wouldn’t bet too much on it! I have a clean backup copy of the project from last weekend, but am hoping I don’t need to revert to that.
Edit: Bug report sent. Can reproduce by opening a new project using URP Core template.