[ShryukGrandhi]

Main | Deploy preview

Summary

The user docs had nothing about about:logging, even though it is a handy way to record Gecko MOZ_LOG output into a profile, especially on Firefox for Android where the page can be used directly on the device.

Fixes #6310

Changes

• Add docs-user/guide-about-logging.md, which covers:
  • why logging to the profiler helps (works in sandboxed processes, one shareable profile, works on Android)
  • how to record a profile with logs (presets, custom MOZ_LOG modules, profiler output)
  • log levels and the profilerstacks option
  • the URL parameters supported by about:logging (preset, modules, threads, output, profiler-preset)
  • using it on Firefox for Android
  • finding the log markers in the profile, and exporting them as text with extractGeckoLogs() from the console
• Link the new page from the sidebar and the Advanced Topics page.
• Add a short pointer from the "Profiling directly on the device" Android guide.

Testing

Docs-only change.

• npx oxfmt --check docs-user/ passes
• npx alex ./docs-user reports no issues