> Most importantly: cached content is no longer shared between domains. This is known as cache partitioning and has been the default in Chrome since October 2020 (v86), Firefox since January 2021 (v85), and Safari since 2013 (v6.1). That means if a visitor visits site A and site B, and both of them load https://public-cdn.example/my-script.js, the script will be loaded from scratch both times.
