Today at work I was sat with two colleagues in the tiny staff room. They're known for their loudness. I'm more senior than they are and I was joining in with little bits of their conversation. Nothing more than pleasantries. One of them then said someething potentially controversial. The other then joined in, but I kept my head down, ate my lunch and looked at my phone. I don't know if the person who said this will get pulled up about it, but I'm on edge at work at the moment. As I was there, as a more senior member of staff, should I have said something about their conversation? Our lunch breaks are unpaid BTW.