SELECT owner_id,
       ts,
       if((owner_id != neighbor(owner_id, 1)) OR (user_agent != neighbor(user_agent, 1)), 0,
          neighbor(ts, 1)) AS LEAD,
       platform_id,
       user_agent,
       operation
FROM (
         SELECT owner_id,
                ts,
                platform_id,
                user_agent,
                date,
                operation
         FROM events
         WHERE (operation LIKE 'app_pageview_%')
           AND (date = '2020-06-07')
           AND ((ts >= 1591488000000) AND (ts <= 1591574399000))
         ORDER BY owner_id ASC,
                  user_agent ASC,
                  ts ASC
         ) AS events
         INNER JOIN
     (
         SELECT *
         FROM (
               SELECT owner_id,
                      platform_id,
                      user_agent,
                      min(ts) AS MIN
               FROM events
               WHERE (operation LIKE 'app_pageview_%')
                 AND (date = '2020-06-07')
                 AND ((ts >= 1591488000000) AND (ts <= 1591574399000))
               GROUP BY owner_id,
                        platform_id,
                        user_agent
               ORDER BY owner_id ASC,
                        user_agent ASC
                  )
         ORDER BY owner_id ASC,
                  user_agent ASC
         ) AS min_events
     ON (min_events.owner_id = events.owner_id) AND (min_events.platform_id = events.platform_id) AND
        (min_events.user_agent = events.user_agent)
WHERE ((ts >= 1591488000000) AND (ts <= 1591574399000))
  AND (date = '2020-06-07')
  AND (operation LIKE 'app_pageview_%')
ORDER BY owner_id ASC,
         user_agent ASC,
         ts ASC;