Greetings. I bought a dimmer switch to replace the standard light switch in my kitchen. I identified that it needed to be a 3 way switch since there are multiple locations to turn these lights on/ off. When I removed the current switch, I noticed that the bare copper ground coming out of the wall isn't connected to anything - it's just covered in a plaster-esque substance. Is this a hazard? Should I be concerned? If this is a problem, would it simply trip the breaker, or should I be worried about a fire?
Thanks! Zac