Boots the kitchen sink on a random port and drives headless Chrome through
the DevTools protocol, running the scenarios in dev/smoke/tests/*.mjs.
Each scenario opens a sink page, performs real clicks and key presses, and
asserts on the resulting DOM, so every hook's behaviour (open/close, arrow
keys, focus management, value changes) is checked end to end.
mix sink.smoke # everything
mix sink.smoke menu tabs # scenarios whose name contains a word
mix sink.smoke --jsonNeeds Google Chrome; set CHROME_BIN to point at another Chromium build.