loader fn not setting response headers like in 1.131.43

const loader = createServerFn()
  .inputValidator(
    z.object({
      token: z.string(),
    }),
  )
  .handler(async ({ data: { token } }) => {
    // simplified
    const headers = new Headers();
    headers.set('Set-Cookie', renderCookie(accessToken));
    setHeaders(Object.fromEntries(headers.entries()));
  });

export const Route = createFileRoute('/auth/callback/magic')({
  validateSearch: zodValidator(
    z.object({
      token: z.string(),
    }),
  ),
  loaderDeps: ({ search }) => ({ token: search.token }),
  loader: async ({ deps }) => loader({ data: { token: deps.token } }),
  component: () => {
    useEffect(() => {
      // some client-side code
    }, []);
    return null;
  },
});

    const headers = new Headers();
    headers.set('Set-Cookie', renderCookie(accessToken));
    setResponseHeaders(headers);