Redirect to the Stripe customer portal.
Which portal screen to open on.
flow names a destination rather than setting a boolean per screen, so a second deep link is a new member instead of a second flag. Absent opens the portal's own home; cancel opens the cancellation screen the cancel dialog sends them to after stating what expires, and payment_method opens the screen that adds the card every charge is made on.
Successful Response
Where to send the browser to manage billing.