What does it mean to have a flat mirror hanging on the fire door of the neighbor's house?

This is to shoot your own fierce and bad things through the mirror. It's not good if your home is across the street. It was taken at your house.

There is a saying in Feng Shui that "when two doors meet, one door will retreat". Because the door is opposite to the door, it is also a kind of suffocation in feng shui. When the two houses are opposite, the weak one will be adversely affected, which should be considered comprehensively according to the strength of the two houses and the rise and fall of the houses. If their house is of this type, many feng shui masters will suggest hanging mirrors on the gate to resist this sense of suffocation.