If you load it into Garmin Connect it generally tells you both- on my most recent ride Garmin Connect says 18mph average for the ride, 18.5 mph moving average, compared to Strava that says 18.1 mph (with no explanation as to moving/total/some odd hybrid).
Based on that wealth of evidence I'm going to say that Strava is telling my my average speed including the time I spent during my stop to take off my gilet.
If you load it into Garmin Connect it generally tells you both- on my most recent ride Garmin Connect says 18mph average for the ride, 18.5 mph moving average, compared to Strava that says 18.1 mph (with no explanation as to moving/total/some odd hybrid).
Based on that wealth of evidence I'm going to say that Strava is telling my my average speed including the time I spent during my stop to take off my gilet.