LCP element analyzer

Everything runs in this tab; the paste is never uploaded and no URL is fetched. The measured routes reproduce what the browser recorded, split the way web.dev defines the LCP phases, and a phase stays unknown when the paste does not carry it, rather than being guessed. The static HTML route is an estimate: it scores markup by declared size and position and cannot see images that scripts add, styles that change at runtime, or which candidate the browser finally picks. Neither route equals the field LCP Google assesses, which comes from real visitors on real devices.