The user is already on my site and logged in so I know their email address. When the access a certain beta feature (with waitlist), I’d like to prompt them to join the waitlist and collect some data about their use case.
However, since we already know who they are, I’d like to add identifying information to the form submission, without having to prompt the user for it. It could be email (preferred), or could be user_id. In either case, the value would come from the javascript environment that is rendering the app and form.
I have not had luck finding this answer in the docs; Google thinks I’m asking about notifications :(