This demo demonstrates the User-Agent request header containing the
desired (either reduced or full) user agent string in the presence of a valid UA Reduction 📖 Deprecation Origin
Trial token for all subsequent requests to the site.
[Request] Request User-Agent:
CCBot/2.0 (https://commoncrawl.org/faq/)
[Response] Server asked for:
Accept-CH:
Origin-Trial:
[Subsequent Request] Client sent:
[…]
[For comparison] Subsequent Request User-Agent:
[…]
Server opt-in origin trials:
What are those origin trials?
-
User-Agent Reduction Origin Trial: User-Agent Reduction is an effort within Chromium to minimize
passive fingerprinting by reducing the entropy in the User-Agent
request header and the Navigator JavaScript APIs
(`navigator.userAgent`, `navigator.platform`).
-
User-Agent Reduction Deprecation Origin Trial: User-Agent Reduction Deprecation is an effort within Chromium to
allow sites that are not yet ready for the reduced UA string to get
the full User Agent string exposed in HTTP requests and in
navigator.userAgent, navigator.appVersion, and navigator.platform
through a deprecation origin trial.