I'm using Wordfence

Wordfence has a feature called Live Traffic that serves an extra blank pageview to every new(?) visitor to check if they are a bot or real traffic.It is reported by our clients that HandL UTM Grabber must have been picking up the wordfence pageview as the first pageview as handl_url.

Proposed Solution: Turn off Live Traffic (switched from ALL to Security Only)

https://www.wordfence.com/help/tools/live-traffic/#traffic-logging-mode