Chrome’s initiative for browser tracking protections (among other things) is called Privacy Sandbox. While Chrome’s pledge to remove third-party cookies has been put on hold, the project includes many other interesting features, such as storage partitioning (see below).
Chrome does not classify classify trackers or domains for the purposes of tracking protection.
Chrome restricts the maximum lifetime of cookies to 400 days.
Chrome restricts the maximum lifetime of cookies to 400 days. Other than that, Chrome does not restrict the use of first-party cookies.
Chrome partitions storage in embedded frames that load content from a cross-site origin.
Example: If siteA.com tries to load an iframe from siteB.com, the latter will have access to its storage (localStorage, for example). However, these storage mechanisms are partitioned between siteA.com and siteB.com. If a second site, such as siteC.com loads a frame from siteB.com, the storage the latter will have access to will not be the same as that available when embedded via siteA.com.
Chrome does not restrict the use of other browser storage in first-party context.
No protections against CNAME cloaking.
Chrome 85 sets the default referrer policy to strict-origin-when-cross-origin. This means that for cross-origin requests (e.g. sub.domain.com to othersub.domain.com, or sub.domain.com to sub.otherdomain.com) the referer HTTP header and document.referrer JavaScript API are truncated to show just the origin of the website making the request. Thus a page such as https://www.domain.com/some-page?param=value would show up just as https://www.domain.com in the referrer records.
On macOS Chrome, the version number in the User Agent string is frozen to 10_15_7 to fix compatibility issues with upgrading to macOS version 11+ (Big Sur). This has obvious privacy implications as well, as the platform version is no longer useful for fingerprinting purposes.
Sample User Agent string when running Chrome 90.0.4430.212 on macOS 11.3.1:
"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/90.0.4430.212 Safari/537.36"