qa-strict-prod-smoke opens the keyless vite preview on each engine, switches once and fails on any page error. qa-strict-cold-chunks reports Cesium.js at a cold Navara start as a known gap instead of a failure.
Every scenario runs through scripts/qa-strict-harness.mjs: each page, frame and worker gets an ordered block list before it runs (paid hosts and routes first, then only the preview, declared fixtures, keyless probes and cached free tile hosts), switches with real input on the picker, and records its assertions per layer and engine. The runner reads the catalog from the live page, fails any layer without an assertion on either engine, can build and serve a keyless checkout itself, and adds rapid, hidden-tab, context-loss, failure-injection, cold-chunk and soak scenarios. The main chunk gets a 1% size budget.
qa-all-layer-switches.mjs now checks once that Puppeteer can start Chrome and that the preview answers, and names PUPPETEER_EXECUTABLE_PATH and npx puppeteer browsers install chrome when it cannot. Each run writes <output>/acceptance.json with the commit, dirty files at both ends, Chrome, Node, base URL, times and, per scenario, status, exit code, duration, covered layer ids and the sha256 of its log. It replaces summary.json.