Email in Checkout is not prefilled when logged in

[beverlytang]

I'm not sure if this is a bug or if I'm not completing the multipass journey correctly. I have successfully implemented user login with multipass. However, the user's email isn't prefilled at checkout.

In CartProvider in App.server.jsx, I added the customerAccessToken. This somewhat works. However, instead of cart.buyerIdentity.email being filled with the customer's email, there is whole cart.customer object with the user's info, while cart.buyerIdentity.email is null.

After the user is logged in via multipass, is this the correct way to pass on to checkout?

I have also tried using the CheckoutButtonMultipass example here but it generates the multipass token again so what I got instead was an error.

[beverlytang]

I thought it was related to multipass but this is a known issue: Shopify/hydrogen#1207.