ua-client-hints VS webappsec-permissions-policy

The Client Hints specification covers a lot of this already - https://wicg.github.io/ua-client-hints/#content-adaptation-u... ... DPR, width, and viewport-width are already available in some browsers. Hopefully other hints will be available soon.

I encourage you to review the decision making and engage in the discussion here: https://github.com/WICG/ua-client-hints

chrome is starting to implement UA-CH, which splits up user agent info into individual headers sent by the client: https://wicg.github.io/ua-client-hints/

As a Firefox/FreeBSD user occasionally annoyed by this nonsense, but not being knowledgeable about modern web standards evolution, I wonder if https://wicg.github.io/ua-client-hints/ will fix this by killing User-Agent headers.

ua-ch might reduce the amount of data browsers send, though it's gonna take a while to move away from regular user agents: https://wicg.github.io/ua-client-hints/

There is a JS companion to this proposal that splits up the information in a similar way

https://wicg.github.io/ua-client-hints/#interface

Thanks for the docs. The examples (2 & 3, https://github.com/w3c/webappsec-permissions-policy/blob/mai...) seem to me to say that search.google.com can’t grant location permissions to an iframe if the parent was forbidden them, but I didn't find an explicit example for what happens if the iframe domain already got permission previously.

As you say the UI for requesting in this case would be weird, and this seems like a big security hole to me, but I can’t see a bit of the spec that explicitly forbids (though I only scanned the doc.)

there is apparently no way to define a default disable either, so to turn off all the random features, the header becomes huge.

https://github.com/w3c/webappsec-permissions-policy/issues/1...

What is happening in w3c?!

This took a fair bit of investigation. I'm not convinced that it's the most well-documented header, in terms of the properties that you can set. Effectively, this is a list of values that determine which permissions are allowed for this website. Given I don't need access to location, camera, microphone or accelerometer. I did have issues finding consistent documentation on this one, so ended up having to combine the Feature-Policy documentation from MDN as well as the permissions policy examples from w3c.

Since Chrome v84 the Chrome team has had a few set backs which has resulted in some changes. In addition, the feature policy header, for delegating the client hints to third parties, has changed name to Permissions-Policy.