Unbounce Confirmation Page
In Unbounce, the "thank you page" is displayed in a layer.
What can be relatively easily set up in Google Ads is not immediately obvious for Facebook Custom Audiences for Unbounce users, as the confirmation page opens in a layer.
Those who use Unbounce typically also have A/B testing activated: Important – depending on which variant is currently being used, the URL of the confirmation page changes each time. The goal is to add all visitors who did not convert to the list to add and to exclude all “buyers” (who have accessed one of the X possible Unbounce A/B test confirmation pages) from the list.