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Mozilla Automation TeamAndreas Farre9 min readintermediate

Tracing algorithms through web specifications

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Summary

The post introduces two tools for navigating the call graph of web specifications: the CLI `webspec-index trace` command and the WebSpec Tracer Firefox extension. It demonstrates how detail flags give a high‑level shape of routes and how the extension lets you interactively build accurate markdown traces for debugging.

  • `webspec-index trace` finds routes between two spec anchors and can output markdown; `--detail edges` shows a concise call‑graph skeleton.
  • `--detail compact` keeps deep links for easy copy‑paste into bug reports.
  • WebSpec Tracer is a Firefox extension that lets you walk algorithms interactively, highlighting links and building markdown traces on the fly.
  • The extension automatically resolves spec prefixes, making cross‑spec boundaries (e.g., HTML → WebIDL) visible.

Browser engineers and spec authors who need to debug or verify algorithmic behavior across HTML, DOM, and related specs should care.

6/10
toolshtmldombrowserspecifications

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