Firefox 40.0

What's new in this version:

- 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 for musical 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

Fixed bugs:
- Bug 1137580 - Do not use system realloc in mozjemalloc-exposed _recalloc.
- Bug 1179262 - Remove PlayPreview usage from PDF viewer.
- Bug 1178058 - Don't convert an expanded principal into inheriting the current principal. Just pretend like the null principal did the load (like LOAD_FLAGS_DISALLOW_INHERIT_OWNER does).