There is a scorch mark in the wall
As long as nothing's smoking &amp; there aren't any flames then, Nope. It's a typical sign of a propane like torch's use for copper plumbing &amp; it could be from a long time ago. The plumber should've used a flame shield &amp; you can clean it off if you'd like. Isopropyl Alcohol or just Swabs usually get rid of it pretty easily.