Prevent 1 action 0 seconds stats

how can i prevent the “1 action 0 seconds” visitor stats?

I have added this code snipped:

window.addEventListener('beforeunload', function(e) {

and i have a mouseleave event arranged.
Both have an effect of the stats, but i have still “1 action 0 seconds” visitors in the stats.

mouseleave prevent only by desktop visitors a “1 action 0 seconds”, because it is a “action”. And this different is visible in the stats. Deskopt mouseleave visitors also not longer “1 action 0 seconds”. Than i have very little bit “1 action <15 seconds”. This, i think, are the effect of beforeunload. And i think this is also only affected by desktop visitor.

I will not use the heartbeat, sorry, it is also not a solution, because, this log only >15 or >5 seconds.

How can i grab mobile device visitor with only 1 action?