We need a Safari extension that annotates all the APIs that don't actually work as intended
https://mastodon.social/@simonbs/114754533531952102

Pro Tip: When you generate promo codes in App Store Connect, the spinner will never stop spinning.
Workaround is to wait until you get the email (which takes anywhere from 5-15 minutes at the moment) then Cancel and go to History section to get the code(s).
My fingers are crossed that an upgrade to the Pentium Pro that's computing these codes gets into next year's budget.