Material giving object a stroke

I’m trying to recreate a 2.79 material in 2.82, but… I don’t even know…

Please help!

I don’t even know either. Not without problematic faces in question, material, and relevant files packed in a supplied blend.

Ok, I tried messing around with some settings, and a figured out that it was the ‘Viewport Denoising’ setting, but could I have an explaination on why that’s happening?