high85%
Server HTML for notFound() is an empty shell without root layout and lang attribute
When a page calls notFound(), Next.js serves a minimal error shell (`__next_error__`) in the server HTML, omitting the root layout, `<html lang>` attribute, and the nearest not-found UI. This breaks accessibility, no-JS clients, and dynamic root layouts, and is inconsistent with the hydrated result. Affects App Router across multiple Next.js versions.