Firefox Beta and Developer Edition
Release Notes

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

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

Improved performance on interactive websites that trigger a lot of restyles

View HTML source in a tab

Remote website debugging over WiFi (no USB cable or ADB needed)

Asynchronous call stacks now allow web developers to follow the code flow through setTimeout, DOM event handlers, and Promise handlers.

Configurable Firefox OS Simulator in WebIDE, to simulate reference devices like phones, tablets, even TVs

CSS filter presets in the Inspector

Ability to save filter presets inside CSS Filter Tooltip

Implemented ES6 Reflect

Support ImageBitmap and createImageBitmap()

Media Source Extension for HTML5 video available for all sites

URLs containing a Unicode-format Internationalized Domain Name (IDN) are not redirected properly, leading to a Server Not Found error.