i am using session start with breakdown of UTM campaign in order to measure subscription funnel. This gives me wrong result when using the breakdown becuase session start event captures the FIRST utm that it finds, in specific cases: when user for example land from direct source, then he subscribes and opens welcome email, then the session start UTM shows the email as source instead of direct (because the direct had no UTM). How can i build a custom event that will only treat the first page view in a session?
