I was using the Tesla mobile connector with a 6 foot extension cord. GFCI outlet, it didn't trip, the 15 amp circuit breaker at the box tripped. Have used this same setup many times in the past, same outdoor outlet, same extension cord, nothing else drawing power from the outlet. 12A current on the screen. Charged for hours no issues.
BUT colder outside this time, around 30F. I wonder if using an extension cord in the cold increases the power draw just enough to trip the 15 amp circuit breaker. Next time will try it without the extension cord or lower the current draw to 10Amp on the screen.