This demo demonstrates the Accept-Language request header and JavaScript
getter containing the reduced string in the presence of a valid Reduce
Accept Language Origin Trial token for all subsequent requests to the
site.
[Request] Request Accept-Language:
Accept-Language: en-US,en;q=0.5
[Response] Server response:
[For comparison] Subsequent resource request Accept-Language:
[…]
[For comparison] Subsequent iframe request Accept-Language:
[…]