We just shipped support for the ugliest part of HTTP: Vary

Cloudflare has added support for the 'Vary' HTTP header, which is used to specify the headers that a server uses to vary its responses. This means that the server can now specify which headers it uses to cache responses, allowing for more efficient caching and reducing the load on the server. The 'Vary' header is often considered the 'ugliest part' of HTTP because it is not well-understood and can be difficult to implement correctly. Cloudflare's support for 'Vary' will make it easier for developers to use it correctly and take advantage of its benefits.