Lighthouse's New Baseline Features Audit: What Developers Should Do With It

You ship a layout that looks clean in Chrome. A week later Safari users report a broken filter panel, or Firefox drops a CSS feature your design system assumed was safe. The Performance score on PageSpeed Insights still looks fine, because speed and interoperability are different questions.

Lighthouse now reports Baseline status for web platform features on a page, including many third-party scripts. Each feature shows Limited, Newly available, or Widely available, with a link to webstatus.dev and a source hint. Treat that list as an inventory with risk labels, not as a new Core Web Vitals threshold.

How we triage it on client sites:

• Collect every Limited row first on money URLs; name an owner and a fallback before go-live

• Treat Newly available as an audience check, not a silent ship in the theme pull request

• Escalate third-party Limited features to the vendor or tag owner instead of rewriting minified vendor code

• Keep Best Practices / Baseline on a separate slide from LCP, INP, and CLS budgets

Scheduled PageSpeed runs catch when a tag or theme change reintroduces Limited features after a quiet week. DevTools is still the place for deep triage of a single finding. Layer monitoring onto the stack you already have.

Read more: Lighthouse Baseline Features audit