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Firefox Release

October 24, 2014

Version 33.0.1, first offered to Release channel users on October 24, 2014

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



  • 33.0.1: Firefox displays a black screen at start-up with certain graphics drivers

  • Various security fixes



Developer Information

Web Platform

  • Windows: On some combination of hardware and drivers, the main window could be black. In this case, update your graphics drivers (1083071)


  • Fix incomplete downloads being marked as complete by detecting broken HTTP1.1 transfers (237623)

  • PDF.js: With some images, wrong colors could show up. Affects a very small number of PDF

  • Some certificate errors cannot be overridden (1042889)

  • Windows: With Avast HTTPS scanning enabled, Firefox will not close correctly (1087674)

  • Windows: Interface may be slow when typing or selecting text (1089183)