👀 Crbug 40211832 – “Implement at-rule for use with @supports.”

Merged CL https://chromium-review.googlesource.com/5972643

This is going to make CSS feature detection so much easier! 🤩 🎉

See https://brm.us/at-rule for details on what it is and how to use.

(The CL landed in main and should be in tomorrow’s Chrome Canary build. You need to enable the Experimental Web Platform features flag to try it)