I was thinking that a service worker could be used: https://bitsofco.de/web-workers-vs-service-workers-vs-worklets/#service-workers https://bitsofco.de/web-wor

I was thinking that a service worker could be used: https://bitsofco.de/web-workers-vs-service-workers-vs-worklets/#service-workers https://bitsofco.de/web-workers-vs-service-workers-vs-workle... If the url returns a 404, check the internet archive, if it’s there then return that otherwise return a 404. If CORS is an issue just proxy the requests via the server that is serving the website.