Mozilla developer preview (Gecko 1.9.3a1) available for download

Editor’s note: Today, Mozilla released a preview of the Gecko 1.9.3 platform for developers and testers. Check out the Mozilla Developer News announcement reposted below.

A Mozilla Developer Preview of improvements in the Gecko layout engine is now available for download. This is a pre-release version of the Gecko 1.9.3 platform, which forms the core of rich Internet applications such as Firefox. Please note that this release is intended for developers and testers only. As always, we appreciate any feedback you may have and encourage users to help us by filing bugs.

This developer preview introduces several new features, including:

  • Support for CSS Transitions. This support is not quite complete: support for animation of transforms and gradients has not yet been implemented.
  • Support for SMIL Animation in SVG. Support for animating some SVG attributes is still under development and the animateMotion element isn’t supported yet.
  • Support for WebGL, which is disabled by default but can be enabled by changing a preference. See this blog post and this blog post for more details.
  • Support for the getClientRects and getBoundingClientRect methods on Range objects. See bug 396392 for details.
  • Support for the setCapture and releaseCapture methods on DOM elements. See bug 503943 for details.
  • Support for the HTML5 History.pushState() and History.replaceState() methods and the popstate event. See bug 500328 for details.
  • Support for the -moz-image-rect() value for <a href="">background-image</a>. See bug 113577 for more details.

and several other significant changes, including:

  • On Mac OS X, we render text using Core Text rather than ATSUI.
  • We rewrote major parts of the code for handling scrolling. See bug 526394 for details.
  • We rewrote the way a snapshot of a document is taken in order to print or print preview. See bug 487667 for details.
  • We made significant changes to table border handling. See bug 452319 and bug 43178 for details.
  • We made various architectural changes to improve Web page performance.

More information on these changes is in the release notes, as well as the Upcoming Firefox features for developers article on the Mozilla Developer Center.

Please use the following links when downloading this Mozilla Developer Preview:

About Alix Franquet

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  1. James John Malcolm

    It’s great that there’s a special build for Devs being promoted – but how different is this from current minefield builds, gecko-wise?

    February 10th, 2010 at 16:43

  2. Boris

    James, it’s not. It’s just a minefield build that doesn’t have any obvious breakage, like any other alpha we ship.

    February 10th, 2010 at 17:19

  3. Brett Zamir

    Wow, I’m SMILing now…

    February 10th, 2010 at 21:43

  4. Wes

    very nice… i’m testing css transitions!

    February 13th, 2010 at 09:20

  5. Benjamin Meyer

    Been working on a little css3 game that is based around transitions. Looks like FF is still missing a few thing (I never seem to get the endTransitionEvent), but getting very close. I look forward to the next release.

    February 16th, 2010 at 23:14

  6. Dan Welsh

    This is the Best Browser I have ever had the pleasure to use. My quest is over.
    Will this ever be ported for 64Bit Intel Macs? I know Josh Aas was working on one.
    Your Humble Lab Rat

    March 2nd, 2010 at 06:50

  7. […] did an a1 release about three weeks ago in order to get testing on some of the new web developer features (which […]

    March 5th, 2010 at 13:30

  8. sn123


    I am new to Gecko , I want to embed this with my J2ee application .
    Can anybody give me some idea about it , any helpful links …


    March 13th, 2010 at 09:07

  9. […] information for developers already has me getting my hopes up. Some of the preliminary reviews of Firefox 4.0 Beta 1 are […]

    July 2nd, 2010 at 10:02

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