Firefox 41 is scheduled to release on September 22 for Windows, Mac and Linux. Adblock Plus users see memory improvements in version 41. This version includes only small improvements and changes, nothing significant unless you’re an ABP user.

What’s new in Firefox 41

No 64-bit Firefox for Windows this time too

64-bit Firefox version for Windows is not available with this release as well, expect Mozilla to ship it with flash sandboxing with Firefox 42.

Ability to set a website as custom new tab has been gone

Mozilla has found browser.newtab.url preference being abused, they’ve removed it. But you can set a custom new tab page by using the add-ons available on AMO.

The company has postponed the deadline for extension signing to Firefox 43, so Mozilla won’t enforce signing requirement in Firefox 41 and 42 versions.

Firefox 41

Preference available and works to prevent auto playing of HTML5 videos

By changing media.autoplay.enabled about:config preference value to ‘false’, you can able to stop HTML5 videos from auto playing in Firefox browser.

Microsoft Edge browser data import

This version of Firefox’s import wizard supports  import of Edge browser bookmarks and cookies into the browser.

Firefox import wizard with Microsoft Edge option

Official change log

New features:

  • SVG images can be used as favicons
  • Enhance IME support on Windows (Vista +) using TSF (Text Services Framework)
  • Ability to set a profile picture for your Firefox Account
  • Firefox Hello now includes instant messaging
  • Improved box-shadow rendering performance.
  • Memory overhead of AdBlock Plus has been greatly reduced

What’s changed

  • WebRTC now requires perfect forward secrecy
  • Improved image decoding with performance up to twice as fast on some devices especially while scrolling
  • WARP is disabled on Windows 7
  • Smoother and more reliable CSS animations via asynchronous animations
  • MessageChannel and MessagePort API enabled by default


  • Added support for the transform-origin property on SVG elements
  • Copy/Cut Web content from JavaScript to the OS clipboard with document.execCommand(“cut”/”copy”)
  • Implemented Cache API for querying named caches that are accessible Window, Worker, and ServiceWorker
  • CSS Font Loading API enabled by default
  • Navigator.onLine now varies with actual internet connectivity (Windows and Mac OS X only)


  • Removed support for binary XPCOM components in extensions, use addon SDK “system/child_process” pipe mechanism for native binaries instead
  • Network requests can be exported in HAR format
  • Quickly add new CSS rule with New Rule button in the Inspector
  • Screenshot a node or element from markup view with the Screenshot Node context menu item
  • Copy element CSS rule declarations with the Copy Rule Declaration context menu item in the Inspector
  • Pseudo-Class panel in the Inspector
  • Picture element does not react to resize/viewport changes

Firefox 41 release notes