Download Mozilla Firefox 31.0

Mozilla has released version 31 of its web browser Firefox. In version 31, Firefox is able to open .ogg media files and PDF documents in Windows, among others. In addition, new tabs get a search field and malware is automatically blocked when it lands in the download folder. Below is the complete overview of the improvements made in version 31:

New

• Add the search field to the new tab page
• Support of Prefer:Safe http header for parental control (learn more)
• mozilla::pkix as default certificate verifier (learn more)
• Block malware from downloaded files (learn more)
• Partial implementation of the OpenType MATH table (section 6.3.6) see documentation about mathematical fonts and the MathML Torture Test for details
• audio/video .ogg and .pdf files handled by Firefox if no application specified (Windows only)
• Upper Sorbian [hsb] local added

Changed

• Removal of the CAPS infrastructure for specifying site-specific permissions (via capability.policy.* preferences). Most notably, attempts to use this functionality to grant access to the clipboard will no longer work. The sole exception is the checkloaduri permission, which may still be used as before to allow sites to load file:// URIs.

HTML5

• WebVTT implemented and enabled (learn more)
• CSS3 variables implemented (learn more)

Developer

• Developer Tools: Add-on Debugger (learn more)
• Developer Tools: Canvas Debugger (learn more)
• New Array built-in: Array.prototype.fill() (learn more)
• New Object built-in: Object.setPrototypeOf() (learn more)
• CSP 1.1 nonce-source and hash-source enabled by default
• Developer Tools: Eyedropper tool added to the color picker (learn more)
• Developer Tools: Editable Box Model (learn more)
• Developer Tools: Code Editor improvements (learn more)
• Developer Tools: Console stack traces (learn more)
• Developer Tools: Copy as cURL (learn more)
• Developer Tools: Styled console logs (learn more)
• navigator.sendBeacon enabled by default (learn more)
• Dialogs spawned from the unforeunload event no longer block access to the rest of the browser

Fixed

• Search for partially selected link text from context menu (985824)

Known Issues

• Slow shut downs lead to ‘Firefox is already running’ warning (see 966469 and 985655)
• PDF.js: With some fonts, some characters might not be displayed. Affects a very small number of PDF (1028735)
• Mac OS X and Windows: Citrix Receiver no longer works. As a workaround, mark the plugin as Always Enable in the addon manager (1025627)
• GNU/Linux and Windows XP: Google Maps Street View displays a black screen (1034593). Resolved in v32.0a2
• Mac OS X: cmd-L no longer opens a new window when no window is available (1008793). Resolved in v32.0a2

The following downloads are available:
Mozilla Firefox 31.0 for Windows (English)
Mozilla Firefox 31.0 for Linux (English)
Mozilla Firefox 31.0 for OS X (English)
Mozilla Firefox 31.0 for Windows (English)
Mozilla Firefox 31.0 for Linux (English)
Mozilla Firefox 31.0 for OS X (English)
Mozilla Firefox 31.0 for Windows (Frisian)
Mozilla Firefox 31.0 for Linux (Frisian)
Mozilla Firefox 31.0 for OS X (Frisian)