Open UI

Check here BEFORE you install a headless primitive — if the control you need is a popover, a dialog, an invoker, or a customizable select, the platform may already do it and Open UI's explainer tells you the exact attribute surface and browser support. The `.research` pages are the best machine-readable answer to 'what should I call this part?' because they tabulate real slot and part names across Carbon, Material, Fluent, and friends, which is exactly what you want when naming props for a new component. Two traps: an explainer is a proposal, not a shipped feature, so always confirm graduation status before generating code from one, and the repo carries a W3C contributor agreement rather than a normal OSS licence, so do not copy prose wholesale.

Why it is here. It is the only entry in this index that shapes the browser itself, and the reason 'just use the native element' is now a defensible answer for popovers, dialogs, and selects. Its cross-system component matrix is a naming authority nothing else matches.