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Firefox Beta and Developer Edition
Release Notes

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.

39.0beta Firefox Beta

May 28, 2015

Version 39.0beta, first offered to Beta channel users on May 28, 2015

New

Fixed

  • Improve performance of IPv6 fallback to IPv4

  • Fix incomplete downloads being marked as complete by detecting broken HTTP1.1 transfers

  • Security state indicator on a page now correctly ignores loads caused by previous pages

  • Fixed an issue where a Hello conversation window would sometimes fail to
    open

Changed

  • Removed support for insecure SSLv3 for network communications

  • NPAPI Plug-in performance improved via asynchronous initialization

  • Performance of displaying dashed lines is improved (Mac OS X)

  • Malware detection service for downloads now covers common Mac file types

Developer

Web Platform

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