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Release Notes tell you what’s new in Firefox. As always, we welcome your feedback. You can also file a bug in Bugzilla or see the system requirements of this release.

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Firefox for Android Aurora

May 15, 2015

Version 40.0a2, first offered to Aurora channel users on May 15, 2015


  • Support for Android Presentation API for screen casting

  • Added protection against unwanted software downloads

  • Long press on back/forward navigation buttons in app menu to bring up history list


  • JPEG images use less memory when scaled and can be painted faster

  • Support for running animations of 'transform' and 'opacity' on the compositor thread

  • Sub-resources can no longer request HTTP authentication, thus protecting users from inadvertently disclosing login data


  • Removed support for binary XPCOM components in extensions, use addon SDK "system/child_process" pipe mechanism for native binaries instead

  • Open links from Android applications in the same tab via EXTRA_APPLICATION_ID

Developer Information

Web Platform