oh
https://developer.mozilla.org/en-US/docs/Web/Privacy/Privacy_sandbox/Partitioned_cookies
CHIPS is similar to the state partitioning mechanism implemented by Firefox. The difference is that state partitioning partitions cookie storage and retrieval into separate cookie jars for each top-level site, without a mechanism to allow opt-in to third-party cookies if desired. As browsers start to phase out third-party cookie usage, there are still valid, non-tracking uses of third-party cookies that need to be permitted while developers begin to handle this change.
so this adds a setting to allow a site access to shared 3rd party cookies, when the site supports the feature?
Based on Mozilla’s documentation, it looks like CHIPS only applies to “cross site” cookies that are just accessible on different subdomains of the same site. A third party cookie could share data between a.site.example and b.site.example if it asked nicely, but not on site2.example.
If this isn’t about it subdomains exclusively, it’s not apparent to me. But it’s all pretty confusing, and CHIPS appears to be just one minor thing that Google introduced when they were creating Privacy Sandbox back in 2022. (You know, to facilitate the total removal of third-party cookies, something they eventually backtracked on anyway.)
