The majority of items mentioned in the article are still in the earliest stages of the standardisation process and haven't even had their specifications finalis

The majority of items mentioned in the article are still in the earliest stages of the standardisation process and haven't even had their specifications finalised yet (see overview at https://www.w3.org/Style/CSS/current-work https://www.w3.org/Style/CSS/current-work). Having access to these cool new features so early on is nice, of course, but be ready and willing to deal with possible breaking changes or even future removal. Here's a recent example of once such breaking API change in the `:has()` selector spec being discussed on the Firefox tracker: https://bugzilla.mozilla.org/show_bug.cgi?id=418039#c44 https://bugzilla.mozilla.org/show_bug.cgi?id=418039#c44. It will be interesting to see how the other browsers that have already released the outdated implementation to production deal with this.