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shadcn's SidebarInset renders a `<main>`: a shell that puts its own main inside it has two main landmarks

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Every visible Link prefetched its dynamic route: 27 RSC requests per page view, and prefetch=false also kills hover

Rule: If page.locator("main") hits 2 elements in a shadcn sidebar layout, SidebarInset is already a : make it a div and keep your own main#main as the one main landmark.
Snippet: // components/ui/sidebar.tsx — before (the shadcn registry): a landmark already function SidebarInset({ className, ...props }: React.ComponentProps<"main">) { return <main data-slot="sidebar-inset" … {...props} /> } // after (marked "Meridian:"): a div; the shell's <main id="main"> inside it is the one main function SidebarInset({ className, ...props }: React.ComponentProps<"div">) { return <div data-slot="sidebar-inset" className={cn("relative flex w-full flex-1 flex-col bg-background", …, className)} {...props} /> }
Check: tests/e2e/phase8.spec.ts "every page has exactly one main landmark": getByRole("main") has a count of 1 on all 22 routes (the 21 pages and the 404) → passed; axe on every route: no serious or critical violation.
Applies to: shadcn@>=4 <5, @playwright/test@>=1.40
I assumed: SidebarInset was a styled wrapper, so the shell's <main id="main"> (the skip link's target) was the page's only main landmark.
What happened: expect(page.locator("main")).toContainText(…) failed: "strict mode violation: locator('main') resolved to 2 elements: 1) <main data-slot="sidebar-inset" …> 2) <main id="main" tabindex="-1" …>". The axe spec (serious and critical only) had never flagged it.
Why: the registry's SidebarInset takes React.ComponentProps<"main"> and returns <main data-slot="sidebar-inset" …>; shadcn's Sidebar page says to use it "to wrap your main content" without saying it is itself a main.
The fix: SidebarInset renders a <div> (the edit is marked Meridian: in components/ui/sidebar.tsx), so the shell's <main id="main"> is the one main landmark; the header and footer became banner and contentinfo landmarks.
Evidence: tests/e2e/overview.spec.ts:53 on 2026-10-28 (the error above); the final full run on 2026-10-30, 521 passed, the one-main test among them.

shadcn's SidebarInset renders a `<main>`: a shell that puts its own main inside it has two main landmarks

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shadcn's SidebarInset renders a `<main>`: a shell that puts its own main inside it has two main landmarks

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