diff --git a/ui/index.html b/ui/index.html
index 1c62d32cf83e..dcb6876ea4fb 100644
--- a/ui/index.html
+++ b/ui/index.html
@@ -11,7 +11,7 @@
     <link rel="icon" type="image/svg+xml" href="/favicon.svg" />
     <link rel="icon" type="image/png" sizes="32x32" href="/favicon-32.png" />
     <link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon.png" />
-    <link rel="manifest" href="/manifest.webmanifest" />
+    <link rel="manifest" href="/manifest.webmanifest" crossorigin="use-credentials" />
     <script>
       // Configure Zod before module evaluation so its JIT probe cannot violate strict CSP.
       globalThis.__zod_globalConfig ??= {};
diff --git a/ui/src/app/mount-fallback.test.ts b/ui/src/app/mount-fallback.test.ts
index 8149cbfead20..5f544d92beae 100644
--- a/ui/src/app/mount-fallback.test.ts
+++ b/ui/src/app/mount-fallback.test.ts
@@ -9,8 +9,12 @@ const indexHtmlPath = path.resolve(
 );
 type TestWindow = Window & typeof globalThis;
 
+async function readIndexHtml(): Promise<string> {
+  return readFile(indexHtmlPath, "utf8");
+}
+
 async function readIndexHtmlWithDelay(delayMs: number): Promise<string> {
-  const html = await readFile(indexHtmlPath, "utf8");
+  const html = await readIndexHtml();
   return html.replace(
     'data-openclaw-mount-timeout-ms="12000"',
     `data-openclaw-mount-timeout-ms="${delayMs}"`,
@@ -74,6 +78,15 @@ function requireElementById<T extends HTMLElement>(
   return element;
 }
 
+describe("Control UI document shell", () => {
+  it("requests the web app manifest with credentials", async () => {
+    const parsed = new DOMParser().parseFromString(await readIndexHtml(), "text/html");
+    const manifest = parsed.querySelector<HTMLLinkElement>('link[rel="manifest"]');
+
+    expect(manifest?.getAttribute("crossorigin")).toBe("use-credentials");
+  });
+});
+
 describe("Control UI mount fallback", () => {
   afterEach(() => {
     document.body.innerHTML = "";
diff --git a/ui/src/e2e/pwa-manifest-credentials.e2e.test.ts b/ui/src/e2e/pwa-manifest-credentials.e2e.test.ts
new file mode 100644
index 000000000000..6ca9a2a95778
--- /dev/null
+++ b/ui/src/e2e/pwa-manifest-credentials.e2e.test.ts
@@ -0,0 +1,162 @@
+// Control UI tests prove real PWA manifest loading through an HTTP Basic Auth proxy.
+import { createServer, type IncomingMessage, type Server, type ServerResponse } from "node:http";
+import type { AddressInfo } from "node:net";
+import { expect, it } from "vitest";
+import { createChatFlowE2eSuite, installMockGateway } from "./chat-flow.test-support.ts";
+
+type ManifestRequest = {
+  authorized: boolean;
+  status: 200 | 401;
+};
+
+type AuthenticatedProxy = {
+  baseUrl: string;
+  close: () => Promise<void>;
+  manifestRequests: ManifestRequest[];
+};
+
+const httpCredentials = {
+  password: "pwa-e2e-test-password",
+  username: "pwa-e2e-test-user",
+};
+const unforwardedHeaders = new Set([
+  "cache-control",
+  "connection",
+  "content-encoding",
+  "content-length",
+]);
+
+async function startAuthenticatedProxy(upstreamBaseUrl: string): Promise<AuthenticatedProxy> {
+  const manifestRequests: ManifestRequest[] = [];
+  const expectedAuthorization = `Basic ${Buffer.from(
+    `${httpCredentials.username}:${httpCredentials.password}`,
+  ).toString("base64")}`;
+
+  const server = createServer((request, response) => {
+    void forwardAuthenticatedRequest({
+      expectedAuthorization,
+      manifestRequests,
+      request,
+      response,
+      upstreamBaseUrl,
+    }).catch(() => {
+      if (!response.headersSent) {
+        response.writeHead(502, { "Cache-Control": "no-store" });
+      }
+      response.end();
+    });
+  });
+
+  await listenOnLoopback(server);
+  const address = server.address();
+  if (!address || typeof address === "string") {
+    throw new Error("HTTP Basic Auth proof proxy did not expose a loopback port");
+  }
+
+  return {
+    baseUrl: `http://127.0.0.1:${address.port}/`,
+    close: () =>
+      new Promise<void>((resolve, reject) => {
+        server.close((error) => (error ? reject(error) : resolve()));
+      }),
+    manifestRequests,
+  };
+}
+
+async function listenOnLoopback(server: Server): Promise<AddressInfo> {
+  return new Promise((resolve, reject) => {
+    server.once("error", reject);
+    server.listen(0, "127.0.0.1", () => {
+      const address = server.address();
+      if (!address || typeof address === "string") {
+        reject(new Error("HTTP Basic Auth proof proxy did not expose a loopback port"));
+        return;
+      }
+      resolve(address);
+    });
+  });
+}
+
+async function forwardAuthenticatedRequest(params: {
+  expectedAuthorization: string;
+  manifestRequests: ManifestRequest[];
+  request: IncomingMessage;
+  response: ServerResponse;
+  upstreamBaseUrl: string;
+}): Promise<void> {
+  const { expectedAuthorization, manifestRequests, request, response, upstreamBaseUrl } = params;
+  const requestUrl = new URL(request.url ?? "/", upstreamBaseUrl);
+  const authorized = request.headers.authorization === expectedAuthorization;
+
+  if (requestUrl.pathname === "/manifest.webmanifest") {
+    manifestRequests.push({ authorized, status: authorized ? 200 : 401 });
+  }
+
+  response.setHeader("Cache-Control", "no-store");
+  if (!authorized) {
+    response.writeHead(401, { "WWW-Authenticate": 'Basic realm="OpenClaw PWA E2E"' });
+    response.end("HTTP Basic authentication required");
+    return;
+  }
+
+  const upstream = await fetch(requestUrl, {
+    headers: { Accept: request.headers.accept ?? "*/*" },
+    method: request.method,
+  });
+  response.statusCode = upstream.status;
+  for (const [name, value] of upstream.headers) {
+    if (!unforwardedHeaders.has(name)) {
+      response.setHeader(name, value);
+    }
+  }
+  response.end(request.method === "HEAD" ? undefined : Buffer.from(await upstream.arrayBuffer()));
+}
+
+const suite = createChatFlowE2eSuite();
+
+suite.define(() => {
+  it("loads the installable same-origin PWA manifest through an HTTP Basic Auth proxy", async () => {
+    const proxy = await startAuthenticatedProxy(suite.server.baseUrl);
+    const context = await suite.newBrowserContext({
+      httpCredentials: { ...httpCredentials, origin: new URL(proxy.baseUrl).origin },
+      serviceWorkers: "block",
+    });
+
+    try {
+      const unauthenticated = await fetch(new URL("manifest.webmanifest", proxy.baseUrl));
+      expect(unauthenticated.status).toBe(401);
+      expect(unauthenticated.headers.get("www-authenticate")).toContain("Basic");
+      proxy.manifestRequests.length = 0;
+
+      const page = await context.newPage();
+      await installMockGateway(page);
+      const response = await page.goto(proxy.baseUrl, { waitUntil: "domcontentloaded" });
+      expect(response?.status()).toBe(200);
+
+      // CDP uses Chromium's PWA manifest loader; page.fetch cannot prove link credentials.
+      const session = await context.newCDPSession(page);
+      const manifest = await session.send("Page.getAppManifest");
+
+      expect(proxy.manifestRequests.length).toBeGreaterThan(0);
+      expect(proxy.manifestRequests.filter((request) => !request.authorized)).toEqual([]);
+      expect(proxy.manifestRequests.every((request) => request.status === 200)).toBe(true);
+      expect(manifest.url).toBe(new URL("manifest.webmanifest", proxy.baseUrl).href);
+      expect(manifest.errors).toEqual([]);
+      expect(JSON.parse(manifest.data ?? "null")).toEqual(
+        expect.objectContaining({ display: "standalone", name: "OpenClaw Control" }),
+      );
+      expect(
+        await page.locator('link[rel="manifest"]').evaluate((link) => ({
+          crossOrigin: (link as HTMLLinkElement).crossOrigin,
+          href: (link as HTMLLinkElement).href,
+        })),
+      ).toEqual({
+        crossOrigin: "use-credentials",
+        href: new URL("manifest.webmanifest", proxy.baseUrl).href,
+      });
+    } finally {
+      await suite.closeBrowserContext(context);
+      await proxy.close();
+    }
+  });
+});