38.0
Firefox Release

May 12, 2015

Version 38.0, first offered to Release channel users on May 12, 2015

We'd also like to extend a special thank you to all of the new Mozillians who contributed to this release of Firefox!

New

  • New tab-based preferences

  • Ruby annotation support

  • Base for the next ESR release.

Fixed

Changed

  • autocomplete=off is no longer supported for username/password fields

  • URL parser avoids doing percent encoding when setting the Fragment part of the URL, and percent decoding when getting the Fragment in line with the URL spec

  • RegExp.prototype.source now returns "(?:)" instead of the empty string for empty regular expressions

  • Improved page load times via speculative connection warmup

Developer

  • Developer Information
  • Optimized-out variables are now visible in Debugger UI

  • XMLHttpRequest logs in the web console are now visually labelled and can be filtered separately from regular network requests

  • WebRTC now has multistream and renegotiation support

  • copy command added to console

Web Platform

  • WebSocket now available in Web Workers

  • BroadcastChannel API implemented

  • Implemented srcset attribute and <picture> element for responsive images

  • Implemented DOM3 Events KeyboardEvent.code

  • Mac OS X: Implemented a subset of the Media Source Extensions (MSE) API to allow native HTML5 playback on YouTube

  • Implemented Encrypted Media Extensions (EME) API to support encrypted HTML5 video/audio playback (Windows Vista or later only)

  • Automatically download Adobe Primetime Content Decryption Module (CDM) for DRM playback through EME (Windows Vista or later only)

unresolved

  • Responsive images do not update when the enclosing viewport changes

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