I think this gos double for Roma it’s like a 6th sense
It’s hard to explain because It almost feels intangible but Roma can always spot other Roma instantly. My grandmother called it “Gypsyy magic” that Roma always have a way of finding each other. I will be walking done a busy sidewalk and see someone one across the street and know they are rom, and than of course then accent will confirm it. The same will Roma are not fooled by imposters.