I'm trying to set some arbitrary values in user profile on user creation based on the incoming request, rather than user input. So instead of having a dropdown that allows the user to select their Locale, I was hoping for a way to have that field pre-populated (and hidden). For example, I was thinking maybe there is a way of sending query string or request parameters to the sign-in page that could be consumed by the sign-in page template javascript to set a value on account creation. But I can't find any documentation or guide that has a similar use case.

I'm trying to use the self-service account creation supported by the hosted sign-in widget. From what I see, the widget has access to the request context, but i'm not seeing anywhere to input a custom parameter from the SP. It supports something like "state", but this is not the correct use case for that. The flow i'm trying to achieve:

1. User visit's SP site
2. User click's sign-in, is redirected to okta hosted sign-in page
3. User clicks "Sign-up"
4. User input's name, pass, email, locale is already set (a hidden form field, or something similar)

Has anyone done anything similar?