Hi - just a DIY homeowner here... 1950's house, 20 amp lighting circuit, total of 10 bulbs and one kitchen exhaust fan on the circuit (all led or florescent bulbs). If I use a regular old 15A breaker everything seems to work fine. If I use a 20A GFCI/AFCI breaker one light fixture consistently trips it (with or without anything else on at the time.) I am not sure whether that fixture is first, last, or in between others on the circuit... What "assumptions" can I make about what is tripping the breaker? "ground fault"? "arc-fault"? - Can I assume that because no other combination of lights trips it, that the fault is either "within" the fixture itself? - or that the fixture is the last on the circuit and the fault is somewhere in that last run of the wire?... Thanks in advance for your patience with this novice!