Immediately after switching the page, it will work with CSR.
Please reload your browser to see how it works.
Which is just going to be in additional to 3rd-party cookies. Google's own study concluded removing 3rd-party cookies loses revenue and "privacy-preserving" tracking increases revenue: https://support.google.com/admanager/answer/15189422 So they'll just do both: https://privacysandbox.com/news/privacy-sandbox-next-steps/
The only one I can think of is if there is a single logical site spread across multiple domains, and you want to be able to maintain a single session across both domains, but are not willing (for aesthetic reasons or technical reasons) to encode this information in the links while moving between domains.
Are there others?
As far as I'm concerned I don't even want first-party cookies to be available when accessed through a third-party context (i.e. if I have a cookie on a.com, and b.com fetches an image from a.com, I don't want that image request to send my a.com cookie).
My preference for this entire discussion is that we eliminate cookies entirely, but use self-signed client certificates very aggressively. When you navigate to a url the user agents sends a client certificate specific to that domain. Any subsidiary fetches use a (deterministic) scoped client certificate specific to the subsidiary domain. All other state tracking is required to be server-side and linked to the certificate. The user can instruct their user agent to reset any of these.
Nothing is private: https://nothingprivate.gkr.pw
More effort ought to be put into how to make web spec to NOT be able track user even if JS is turned on.
Browser vendor Brave, Firefox suppose to privacy browser are NOT doing anything about it.
At this point, do we need to using JS disabled browser to really get privacy on the web?
Section 2: Third party cookies have gotten bad. Ok.
Section 3: There are legitimate use cases that third party cookies currently cover. Also ok. Then they throw in, "Be aware that a set of new technologies which carry minimal risk individually, could be used in combination for tracking or profiling of web users." Yes? Huge scope increase in the document though and all of a sudden we're now talking about tons of tracking technologies in aggregate? The authors move on without further comment.
Section 4: I think the first half is essentially saying that new technology coming online in the web platform will make the third party cookie problem worse, so we should fix it soon. OK, I'm with back with you. Then the document suddenly pivots to proposing general standards for web privacy again, saying that the burden of proof is on the people originating the proposal to, before concluding by saying (apparently without irony?) that justifying the removal of third-party cookies' impact on business is outside of the scope of the document.
I'm missing a ton of cultural context here about how W3C works, so I'm guessing this probably amounts to rough notes that somebody intends to clean up later that I'm being overly critical of, and they didn't expect it to get any traction on hacker news.