Work for Web Browser

npm install stripe-pwa-elements

And defineCustomElements() called once during the bootstrapping of your application.

+ import { defineCustomElements } from 'stripe-pwa-elements/loader';
+ defineCustomElements();

stripe-pwa-elements is created with StencilJS. If you can't understand where defined, please check these docs:

https://stenciljs.com/docs/overviewhttps://stenciljs.com/docs/overview