Firefox 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.
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42.0
Firefox Release
November 3, 2015
We'd also like to extend a special thank you to all of the new Mozillians who contributed to this release of Firefox!
New
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Private Browsing with Tracking Protection blocks certain Web elements that could be used to record your behavior across sites
-
Control Center that contains site security and privacy controls
-
Indicator added to tabs that play audio with one-click muting
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Login Manager improvements:
- Improved heuristics to save usernames and passwords
- Edit and show all logins in line, Copy/Paste usernames/passwords from the Context menu
- Migration imports your passwords to Firefox from Google Chrome for Windows and Internet Explorer; import anytime from the Login Manager
-
WebRTC improvements:
- IPV6 support
- Preferences for controlling ICE candidate generation and IP exposure
- Hooks for extensions to allow/deny createOffer/Answer
- Improved ability for applications to monitor and control which devices are used in getUserMedia
Fixed
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Various security fixes
Changed
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Improved performance on interactive websites that trigger a lot of restyles
Developer
- Developer Information
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View HTML source in a tab
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Remote website debugging over WiFi (no USB cable or ADB needed)
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Asynchronous call stacks now allow web developers to follow the code flow through setTimeout, DOM event handlers, and Promise handlers.
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Configurable Firefox OS Simulator in WebIDE, to simulate reference devices like phones, tablets, even TVs
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CSS filter presets in the Inspector
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Ability to save filter presets inside CSS Filter Tooltip
Web Platform
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Implemented ES6 Reflect
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Support ImageBitmap and createImageBitmap()
-
Media Source Extension for HTML5 video available for all sites
unresolved
-
URLs containing a Unicode-format Internationalized Domain Name (IDN) are not redirected properly, leading to a Server Not Found error.
Get the most recent version
Download Firefox — English (US)
Your system may not meet the requirements for Firefox, but you can try one of these versions:
Download Firefox — English (US)
Your system doesn't meet the requirements to run Firefox.
Your system doesn't meet the requirements to run Firefox.
Please follow these instructions to install Firefox.
- Download Firefox
- Download Firefox
- Download Firefox
- Download Firefox
- Download Firefox
- Download Firefox
- Download Firefox
- Firefox for Android
- Firefox for iOS