It’s hard to speculate about what the flight would have been like if others had been in F. I can’t point to anything that makes me think it was necessarily more lax, but I could imagine that playing a part. That said I had a mask on for takeoff (after I finished my OJ) up until my whiskey arrived. I took it off then and throughout the entire meal, which was a considerable amount of time. I also kept it off while drinking water, which I drank a lot of. Otherwise I put it on or pulled up the baklava/gaiter style mask that I wore while trying to sleep. I didn’t want to make the wonderful staff uncomfortable or put them in a difficult position. We still had plenty of conversations with my mask off as I was mid-meal(s). Of course in some ways I may have been seen as less of a concern even than the Japanese nationals making up most of the pax - as a non-citizen I had had to get a negative test within 72 hours of my flight (and the FA and I had discussed this explicitly while chatting).

On my domestic United leg I took my mask off to eat the provided snacks and the sandwich I had brought on board. Put it back on once I was all done. Wasn’t bothered by anyone for the 15 minutes or so I had it off.