Track Lighthouse performance and accessibility improvements

[reakaleek]

Summary

Track repository-owned improvements identified by a desktop Lighthouse audit of https://www.elastic.co/docs/release-notes/cloud-serverless on 2026-07-21.

Baseline

Category	Score
Performance	61
Accessibility	92
Best Practices	96
SEO	100

Key measurements:

• First Contentful Paint: 0.5 s
• Largest Contentful Paint: 1.0 s
• Total Blocking Time: 962 ms
• Speed Index: 4.7 s
• Cumulative Layout Shift: 0.004
• Transferred payload: 4.39 MiB
• Estimated unused JavaScript: 1.67 MiB

FCP, LCP, and CLS are healthy. The main opportunities are reducing post-paint JavaScript work and transferred code, correcting the pages dropdown semantics, and removing the failed API availability probe.

Scope

Child issues cover independently implementable changes owned by elastic/docs-builder. Verify changes with a production frontend build and a clean/incognito Lighthouse run.

The supplied report warned that browser cache clearing timed out and IndexedDB data was present. It also attributed about 313 KiB of unused JavaScript to a browser extension, so exact scores and byte totals must not be treated as deterministic.

Upstream findings

The following findings are not implemented by this repository and should be raised with the website/global-navigation owner separately:

• The global navigation <ul> contains direct <a> children for Pricing and Docs.
• elastic-nav.js causes about 219 ms of forced reflow and has no production source map.
• MierB-Demi.woff2 lacks an effective font-display policy.
• Unused/minifiable website-search and Google Tag Manager assets are externally built.

Completion criteria

• All repository-owned child issues are resolved or explicitly declined.
• Frontend unit, type, lint, and production build checks pass.
• Lighthouse is rerun in a clean browser profile and before/after results are recorded.