New

Support for Windows 10

New

Added protection against unwanted software downloads

New

Suggested Tiles show sites of interest, based on categories from your recent browsing history

New

Hello allows adding a link to conversations to provide context on what the conversation will be about

New

New style for add-on manager based on the in-content preferences style

New

Improved scrolling, graphics, and video playback performance with off main thread compositing (GNU/Linux only)

New

Graphic blocklist mechanism improved: Firefox version ranges can be specified, limiting the number of devices blocked

Changed

Add-on extensions that are not signed by Mozilla will display a warning

Changed

Smoother animation and scrolling with hardware vsync (Windows only)

Changed

JPEG images use less memory when scaled and can be painted faster

Changed

Sub-resources can no longer request HTTP authentication, thus protecting users from inadvertently disclosing login data

Changed

NPAPI Plug-in performance improved via asynchronous initialization

HTML5

IndexedDB transactions are now non-durable by default

HTML5

Implemented AudioBufferSourceNode.detune to modulate playback rate in cents, a logarithmic unit of measure used formusical intervals

Developer

Improved Performance tools in the developer tools: Waterfall view, Call Tree view and a Flame Chart view

Developer

Console API messages from SharedWorker and ServiceWorker are now displayed in web console

Developer

Inspector now searches across all content frames in a page

Developer

New rules view tooltip in the Inspector to tweak CSS Filter values

Developer

New page ruler highlighting tool that displays lightweight horizontal and vertical rules on a page

Fixed

Kannada text does not display properly in built-in pdf viewer

unresolved

If Firefox is restarted from an add-on install notification, on-going private browsing downloads might be canceled without warning  (1185294)