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44.0beta

Firefox Beta

December 17, 2015

Version 44.0beta, first offered to Beta channel users on December 17, 2015

New

  • Improved warning pages for certificate errors and untrusted connections

  • Enable H.264 if system decoder is available

  • Enable WebM/VP9 video support on systems that don't support MP4/H.264

Fixed

  • Windows XP and Vista screensaver doesn't disable when watching videos (Bug 1193610)

Changed

  • Firefox has removed support for the RC4 cipher

  • To support unicode-range descriptor for webfonts, font matching under Linux now uses the same font matching code as other platforms

  • Firefox will no longer trust the Equifax Secure Certificate Authority 1024-bit root certificate or the UTN - DATACorp SGC to validate secure website certificates

  • Use a SHA-256 signing certificate for Windows builds, to meet new signing requirements

Developer

  • Right click on a logged object in the console to store it as a global variable on the page

  • Visual tools for Animation:

    • View/Edit CSS animation keyframe rules directly in the inspector
    • Visually modify the cubic-bezier curve that drives the way animations progress through time
    • Discover and scrub through all CSS animations and transitions playing on the page
    • Learn more: http://devtoolschallenger.com/
  • Visual tools for Layout and Styles:

    • Display rulers along the viewport to verify size and position and use the measurement tool to easily detect spacing and alignment problems
    • Use CSS filters to preview and create real-time effects like drop-shadows, sepia, etc
    • Learn more: http://devtoolschallenger.com/
  • New memory tool for inspecting the memory heap

  • Service Workers API

  • Built-in JSON reader to intuitively view, search, copy and save data without extensions

  • Jump to function definitions in the debugger with Cmd-Click

  • WebSocket Debugging API and add-on

  • The rule view now displays styles using their authored text,
    and edits in the rule view are now linked to the style editor

  • Add-on signing enforcement

Developer Information