Where do Application User Profile and IdP User Profile come from?

Questions
1

Hello,

I was reading the documenation about Okta Expression Language (https://developer.okta.com/reference/okta_expression_language/#application-user-profile), and I’m quite confused about Application User Profile and IdP User Profile.

The way I understand it is that, when talking about Application User Profile and IdP User Profile in the context of Okta Expression Language, we are reading, retrieving, or referencing those profiles’ attributes and that we are not assigning values to those profile attributes using Okta Expression Language, e.g. in a claim of a token.

So where do the Application User Profile and IdP User Profile’s attributes come from?
How do they get populated? Suppose I have an SPA. Would the SPA call an Okta API or SDK function to populate the application user profile or IdP user profile?

Do the application and IdP user profiles get saved on Okta’s auth server? If I go to https://dev-XXXXXX-admin.oktapreview.com/admin/users, I don’t really see any indication that there can be separate application or IdP user profiles for my users.

2

Under Directory>Profile Editor you can apply mappings for these attributes in each schema

Generally if you have an on-prem directory configured you would apply an expression to map the attribute from AD or LDAP to the user or appuser profile