How do I obtain a PayPal user's payer_id through OpenID Connect?

Question

I'm authenticating a PayPal user using the REST OpenID Connect API, which let's me access the userinfo information for that user.

I'd like to use this information to be able to send money to that user through the Adaptive Payments API. I know I can use their email address for this, but email addresses change, so I'd like to use the accountId field instead, which I believe is the same as the payer_id visible the Express Checkout APIs, and should be a consistent, unique ID.

However, despite the payer_id field being documented in the userinfo response, I don't see that information in the response. I can see user_id, which looks like a URL, and doesn't seem to contain the same identifier.

Is it possible to get a payer_id out of the REST API?

Answer 1

I see from this answer that you have to ask for this attribute:

Can I get payer_id with "Login with Paypal"?