[galaxyLogic]

What if we had a local server running on the same PC, which then relays the request to some shared server on the internet?

[cwillu]

That's what a background worker is: a local server managed by the browser and only accessible to pages of the origin domain.

[galaxyLogic]

I'm thinking using a local http-server instead of web-workers . The local http server would do all the server-logic except also passing data that needs to be shared to a non-local server.