Firefox Profiler Deployment (December 18, 2025)

The latest version of the Firefox Profiler is now live! Check out the full changelog below to see what’s changed:

Highlights:

  • [Florian Quèze/Nazım Can Altınova] Add an importer for the text format taken as input by flamegraph.pl. (#5359)
  • [Valentin Gosu] Add priorityHeader field to network requests (#5707)
  • [Markus Stange] Make binary profile format parsing use Uint8Array instead of ArrayBuffer (#5678)
  • [Nazım Can Altınova] Redirect unpublished url loads to the homepage similar to from-file (#5712)

Other Changes:

  • [Markus Stange] Use a longer test timeout when debugging with VS code. (#5679)
  • [Markus Stange] Move Jest config from package.json to jest.config.js (#5680)
  • [Markus Stange] Use workbox-cli to generate the service worker (#5681)
  • [Nazım Can Altınova] Migrate from Appveyor to GitHub Actions Windows runners (#5660)
  • [Nazım Can Altınova] Remove some unused dependencies (#5696)
  • [Nazım Can Altınova] Update the document links and sections (#5705)
  • [Nazım Can Altınova] Clear selected and expanded call node paths on browser back button if it removes transforms (#5701)
  • [Nazım Can Altınova] Properly type the Map and Set objects (#5623)
  • [Florian Quèze] Improve the import of profiles generated from clang -ftime-trace=file.json (#5714)
  • [Markus Stange] Move React stuff out of marker schema logic module. (#5720)

Big thanks to our amazing localizers for making this release possible:

  • en-CA: chutten
  • en-CA: Paul
  • es-CL: ravmn
  • fr: Théo Chevalier
  • fur: Fabio Tomat
  • ru: berry
  • tr: Selim Şumlu
  • zh-CN: Olvcpr423
  • zh-CN: wxie

Find out more about the Firefox Profiler on profiler.firefox.com! If you have any questions, join the discussion on our Matrix channel!