Firefox Developer Edition

March 8, 2016

Version 47.0a2, first offered to Firefox Developer Edition channel users on March 8, 2016

For more information about Developer Edition please see this MDN article.


  • Embedded YouTube videos now play with HTML5 video if Flash is not installed.

  • Allow no-cache on back/forward navigations for https resources


  • FUEL (Firefox User Extension Library) has been removed. Add-ons relying on it will stop working.


  • Developer Information
  • Implemented Document.scrollingElement to tell which element's scroll attributes reflect the viewport scroll state

  • See Firefox run! Review Firefox performance data in about:performance.

  • Smart multi-line input in the Web Console

  • Custom user agents supported in Responsive Design Mode

  • Simulate Push messages in the Service Workers developer tool

  • View, start,and debug registered Service Workers in the Service Workers developer tool

  • 'Start' button for service workers in about:debugging to start registered Service Workers

  • Tilt is available as extension on AMO

Web Platform

  • WebCrypto: RSA-PSS signature support

  • WebCrypto: PBKDF2 supports SHA-2 hash algorithms

  • cuechange events are now available on TextTrack objects

All Firefox Developer Edition downloads