Log Message:
Update to 20.0

Changelog:
    NEW
    Per-window Private Browsing. Learn more.
    NEW
    New download experience. Learn more.
    NEW
    Ability to close hanging plugins, without the browser hanging
    CHANGED
    Continued performance improvements around common browser tasks (page loads, \ 
downloads, shutdown, etc.)
    DEVELOPER
    Continued implementation of draft ECMAScript 6 - clear() and Math.imul
    DEVELOPER
    New JavaScript Profiler tool
    HTML5
    getUserMedia implemented for web access to the user's camera and microphone \ 
(with user permission)
    HTML5
    <canvas> now supports blend modes
    HTML5
    Various <audio> and <video> improvements
    FIXED
    Details button on Crash Reporter (793972)
    FIXED
    Unity plugin doesn't display in HiDPI mode (829284)
    FIXED
    20.0: Security fixes can be found here

Fixed in Firefox 20
MFSA 2013-40 Out-of-bounds array read in CERT_DecodeCertPackage
MFSA 2013-39 Memory corruption while rendering grayscale PNG images
MFSA 2013-38 Cross-site scripting (XSS) using timed history navigations
MFSA 2013-37 Bypass of tab-modal dialog origin disclosure
MFSA 2013-36 Bypass of SOW protections allows cloning of protected nodes
MFSA 2013-35 WebGL crash with Mesa graphics driver on Linux
MFSA 2013-34 Privilege escalation through Mozilla Updater
MFSA 2013-33 World read and write access to app_tmp directory on Android
MFSA 2013-32 Privilege escalation through Mozilla Maintenance Service
MFSA 2013-31 Out-of-bounds write in Cairo library
MFSA 2013-30 Miscellaneous memory safety hazards (rv:20.0 / rv:17.0.5)