igrigorik/http-client-hints — pull request #34 by yoavweiss (2014-10-20 13:31:43+00:00)
Title: Opt-in should not apply to main document request

Following the discussions at EdgeConf, and in order to enable CH-based HTML manipulations (which hopefully can reduce/eliminate the use of UA sniffing), I'm taking a stab at adding text that makes it a SHOULD for UAs to send all hints on the first request, but lets them make the hints opt-in for subsequent requests.