Firefox Developer Edition

September 20, 2016

Version 51.0a2, first offered to Firefox Developer Edition channel users on September 20, 2016

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


  • Added support for FLAC (Free Lossless Audio Codec) playback

  • Users can view passwords in the save password prompt before saving them

  • Added a zoom button in the URL bar:

    • Displays percent above or below 100 percent when a user has changed the page zoom setting from the default
    • Lets users return to the default setting by clicking on the button
  • Improved video performance for users without GPU acceleration for less CPU usage and a better full screen experience

  • Firefox will save passwords even in forms that do not have “submit” events

  • Added Georgian (ka) and Kabyle (kab) locales


  • Process separation (e10s) now supported on Windows 10 touch screen devices and systems with accessibility tools installed

  • Use 2D graphics library (Skia) for content rendering on Linux

All Firefox Developer Edition downloads