Firefox Release Notes

Firefox Hello with new rooms-based conversations model

New search UI improved and enabled for more locales

Access the Firefox Marketplace from the Tools menu and optional toolbar button

Built-in support for H264 (MP4) on Mac OS X Snow Leopard (10.6) and newer through native APIs

Improved handling of dynamic styling changes to increase responsiveness

Use tiled rendering on OS X

Improved high quality image resizing performance

Various security fixes

Show DOM Properties context menu item in inspector

Reduced resource usage for scaled images

PDF.js updated to version 1.0.907

Non-HTTP(S) XHR now returns correct status code

Support for inspecting ::before and ::after pseudo elements

Computed view: Nodes matching the hovered selector are now highlighted

Network Monitor: New request/response headers view (more info)

Added support for the EXT_blend_minmax WebGL extension

Changed JavaScript 'let' semantics to conform better to the ES6 specification

Resource Timing API implemented

CSS filters enabled by default

Added support for the CSS Font Loading API

WebGL games might not display some textures (see bug 1113633)

Sometimes images don't display when hovered over (see bug 1083113)

Issues affecting RTL in Hello can be found here

Crashes with "Enhanced Steam" extension enabled on Steam websites (see bug 1117873)