no email event registration confirmation when paying via Stripe Checkout

I saw this in mattermost back in September and also have this problem.

With a paid event that includes a email receipt option, configured to use Stripe Checkout, no email confirmation message is sent upon a successful checkout.

When a $0 option is selected, the user is not redirected to Stripe Checkout, and an email is sent. But when a registration option is selected that includes an amount, we are directed to Stripe Checkout and everything works properly except no email confirmation is set.

I'm going to be digging in to try to figure it out - but if anyone sees this and has clues as to where to start, they would be appreciated.