There’s no built-in keystroke collection mechanism with HubSpot forms, and it’s not possible to apply a specific class to a form field through the UI. If I’m reading that article correctly all that needs to happen for Lucky Orange to collect keystrokes is for the input(s) to have the class LoNotSensitive applied. I can’t speak to the Lucky Orange side of things, but the only way to apply a class to a HubSpot form input would be to target the form inputs and add the class with Javascript after the form has loaded.