Should I be concerned

I was doing an oil change in my neighbors 2019 1.5t accord with about 50k miles on it. I noticed this coffee colored “sludge” on the top of the oil cap. I’m not sure what it is. Anyone know if this is okay?

I was doing an oil change in my neighbors 2019 1.5t accord with about 50k miles on it. I noticed this coffee colored “sludge” on the top of the oil cap. I’m not sure what it is. Anyone know if this is okay?