Why does stripe.js file load on all my site's pages?
It is normal to think that script sources shouldn't load on every page, however Stripe actually recommends this due to security and fraud prevention.
Stripe recommends this:
"Include the Stripe.js script on each page of your site—it should always be loaded directly from https://js.stripe.com, rather than included in a bundle or hosted yourself.
To best leverage Stripe’s advanced fraud functionality, include this script on every page, not just the checkout page. This allows Stripe to detect anomalous behavior that may be indicative of fraud as customers browse your website."