A committed harness (Fixtures/complete-page-harness.cjs) executes the served page's inline script against a simulated browser; tests pin that the fragment is dropped before the post, an error status never submits, and the code is read only from the fragment. Node is required on PATH; a missing Node fails, it does not skip.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
