Spec: https://www.w3.org/TR/payment-request-1.1/

https://www.w3.org/blog/news/archives/9644

(DE) https://www.heise.de/news/Bezahlen-im-Browser-W3C-legt-ersten-Entwurf-fuer-Payment-Request-API-1-1-vor-7190323.html

Not the same as https://caniuse.com/payment-request, at least currently - they talk about that in https://www.w3.org/TR/payment-request-1.1/#sotd

The W3C published Payment Request API 1.0 as a Proposed Recommendation in September 2021.

…

If Payment Request API 1.0 advances to Recommendation, the Editors will determine whether it would be preferable to fold these changes into an evolving 1.0 Recommendation, or to continue to nurture a 1.1 branch. At the current time, we do not need to make that decision.