To edit a popup on your sales page in GHL and ensure it collects user details, go to Sites > Forms and create a form for the popup. Once the form is created, navigate to Automation and set the form as the trigger.
This ensures that any automation you’ve set up will fire once the form is completed. Popups are typically used to collect details from users, which can then feed into your automation funnel for follow-ups if they don’t complete a purchase.