Make sure a Stripe account is selected under “Payment account used on this form”.
Toggle on the option “Include Stripe receipt email in the checkout”.
Now your customers will be asked to enter their email address for the receipt in the checkout page, and will be auto-sent a Stripe receipt upon successfully being charged.
Gotchas
Note that this is only available for the Stripe Credit Card checkout. If you are using a different payment source (e.g. iDEAL pay), then the email address may not be captured.
Passing information from your form to the Stripe receipt is currently not supported.