User Behavior

You can target users based on their session depth (number of pageviews in the current session), and whether they are a first time or repeat visitor. Surveys are targeted to “All visitors” by default.

Some browsers have a 'back forward cache' that stores the page as it was and displays it from cache (exactly as it was when you left it). In this case, our servers aren't being called and we aren't sending an incremental impression, but rather the visitor is returning to the page in its previous state.