test(e2e): L5 hard-nav instant shell for marketing routes

e2e/instant-marketing-hard-nav.spec.ts

@@ -0,0 +1,85 @@
+import { instant } from "@next/playwright";
+import { type APIRequestContext, expect, test } from "@playwright/test";
+
+import { dismissCookieBannerIfVisible } from "./helpers/dismissCookieBanner";
+
+/** Instant MPA mode includes prerendered marketing copy only with a production PPR shell. */
+async function hasProductionInstantShell(
+  request: APIRequestContext,
+  path: string,
+  expectedSnippet: string,
+): Promise<boolean> {
+  const response = await request.get(path, {
+    headers: { cookie: "next-instant-navigation-testing=1" },
+  });
+  if (!response.ok()) {
+    return false;
+  }
+  const html = await response.text();
+  return html.includes(expectedSnippet);
+}
+
+/**
+ * L5: hard navigation (MPA reload) instant shell for default-locale marketing.
+ * Skips under `next dev` (instant MPA bails to CSR); runs on production / preview builds.
+ */
+test.describe("instant marketing hard navigation (L5)", () => {
+  test.describe.configure({ mode: "serial" });
+
+  test.beforeAll(async ({ request }) => {
+    const shellReady = await hasProductionInstantShell(
+      request,
+      "/",
+      "Your code, frame by frame.",
+    );
+    test.skip(
+      !shellReady,
+      "Requires production PPR shell (instant MPA CSR-bails in next dev)",
+    );
+  });
+
+  test("home hero shell is instant on hard navigation", async ({ page }) => {
+    test.setTimeout(120_000);
+
+    await page.goto("/");
+    await dismissCookieBannerIfVisible(page);
+
+    await instant(page, async () => {
+      await page.reload({ waitUntil: "domcontentloaded" });
+      await expect(page.getByRole("heading", { level: 1 })).toContainText(
+        "Your code, frame by frame.",
+        { timeout: 30_000 },
+      );
+    });
+  });
+
+  test("privacy shell is instant on hard navigation", async ({ page }) => {
+    test.setTimeout(120_000);
+
+    await page.goto("/privacy");
+    await dismissCookieBannerIfVisible(page);
+
+    await instant(page, async () => {
+      await page.reload({ waitUntil: "domcontentloaded" });
+      await expect(page.getByRole("heading", { level: 1 })).toHaveText(
+        "Privacy Policy",
+        { timeout: 30_000 },
+      );
+    });
+  });
+
+  test("daily shell is instant on hard navigation", async ({ page }) => {
+    test.setTimeout(120_000);
+
+    await page.goto("/daily");
+    await dismissCookieBannerIfVisible(page);
+
+    await instant(page, async () => {
+      await page.reload({ waitUntil: "domcontentloaded" });
+      await expect(page.getByRole("heading", { level: 4 })).toContainText(
+        "Not sure what to solve?",
+        { timeout: 30_000 },
+      );
+    });
+  });
+});

vibe-docs/Instant-Navigations-Design.md

@@ -210,7 +210,7 @@ Visited routes can stay mounted in hidden Activity boundaries. Heavy clients mus
 | Pyodide worker | `pythonRunner.release()` via `usePlaygroundRuntimeRelease` | Playground |
 | Shared primitive | `useDeferredClientMount(onCleanup?)` | Reuse for future widgets |
 
-E2e: `home-webgl-nav`, `playground-monaco-nav`, `home-hero-preview-nav`.
+Hard navigation (L5): production PPR shell validated by `instant-marketing-hard-nav` e2e (skips under `next dev`); `DocumentLocaleSync` keeps `lang`/`dir` aligned after hydration.
 
 ---
 

vibe-docs/Instant-Navigations-TODO.md

@@ -49,5 +49,6 @@
 - [x] Activity lifecycle shells: `WebGLCanvasShell`, `CodeRunner`, shared `useDeferredClientMount`
 - [x] E2e: landing WebGL recovery, playground Monaco nav, Pyodide `release()` on playground leave, hero preview after instant nav
 - [x] `pythonRunner.release()` on playground Activity hide; benchmark RAF throttle cancel on unmount
-- [ ] Initial page-load instant shell (hard navigation) — follow-up
+- [x] Initial page-load instant shell (hard navigation) — `e2e/instant-marketing-hard-nav.spec.ts` (prod/preview PPR; skips in dev)
+- [ ] Session / device hints in Suspense for fuller marketing instant shell — follow-up
 - [ ] Playground/profile instant adoption (optional)

vibe-docs/Locale-Migration-Design.md

@@ -94,8 +94,9 @@ Pages `i18n` auto-redirects `/en/*` → unprefixed URLs, so **`next.config` rewr
 2. ~~Root `headers()` locale read~~ — direct read in `RootHtmlShell` with root `instant = false` (correct RTL; no Suspense fallback flash).
 3. ~~Single provider mount + cached i18n~~ — one `AppRootLayoutClient`; `'use cache'` on translations; locale layouts `instant = false`.
 4. ~~`@next/playwright` `instant()` tests~~ — marketing client navigations (`e2e/instant-marketing-nav.spec.ts`).
-5. Initial page-load instant shell (hard navigation) — follow-up.
-6. Playground/profile instant adoption — optional.
+5. ~~Initial page-load instant shell (hard navigation)~~ — static `RootHtmlShell`, `DocumentLocaleSync`, hard-nav e2e (auto-skips in dev).
+6. Session / device hints in Suspense for fuller marketing shell — optional follow-up.
+7. Playground/profile instant adoption — optional.
 
 ---