New Web Developer Features in Deer Park Alpha 1

HTML

Elements with tabindex="-1" should be focusable

Elements with a negative tabindex attribute can now have focus, even though they are not in the tab order.

Object should submit

In accordance with the HTML4 specification, <object> elements can now be submitted as part of a form.

CSS

CSS2 quotes nesting

Starting with this release, the CSS2 quotes property is fully supported, with the correct quote (depending on the nesting level) being used for open-quote and close-quote.

CSS3 :only-child

This CSS3 selector allows selecting an element that has no other elements as siblings in the DOM.

CSS3 columns

An experimental implementation of the proposed CSS3 multicolumn layout draft. This allows easily doing newspaper-like multicolumn presentation.

CSS3 overflow-x and overflow-y properties

These properties can be used to control the overflow behavior in the horizontal and vertical directions somewhat independently. For example, overflow in the horizontal direction could be hidden while overflow in the vertical direction can be scrolled to.

CSS3 cursors

More mouse cursor names are now supported.

URI values on CSS cursor properties

On Windows, OS/2 and Linux (Gtk+ 2.x) one can now use an arbitrary image as the mouse cursor while a given DOM node is being hovered. Any image format supported by Gecko can be used for the image (SVG, animated GIF, and ANI cursors are not supported).

CSS outline property

CSS outlines can now be used. These differ from borders in that they don't affect the page layout.

-moz-outline-radius

CSS outlines can now have rounded corners.

Counters in CSS-generated content

CSS2 counters are now completely supported (the implementation doesn't match the current CSS2.1 draft, but matches the upcoming one). This allows automatic numbering of sections, headings, and so forth via stylesheets.

JavaScript and DOM

Array extras

New methods have been added to the Array object to facilitate common tasks. See JavaScript 1.5 Array Object.

document.open("text/plain")

Text written in new documents created with document.open("text/plain") is now treated as text rather than HTML, so line breaks will remain intact and tags will not be parsed.

XML Events

"XML Events" is a W3C specification to provide XML languages with the ability to integrate declarative event listeners and event handlers.

Canceling keydown

Canceling the keydown event now properly cancels any corresponding keyup/keypress events, per the DOM specification.

Accessibility APIs for DHTML

Mozilla now allows DHTML authors to add role and state semantics to custom elements, and exposes that information via MSAA and ATK.

DHTML Performance Fixes

A number of changes were made to significantly improve DHTML speed and smoothness.

Graphics

SVG Support

SVG is W3C specification providing resolution-independent scalable vector graphics, along with a DOM. A technology preview of native SVG support is included in this release. Currently a subset of SVG 1.1 Full, missing functionality includes filters, declarative animation, and SVG defined fonts.

Canvas Support

<canvas> is a scriptable bitmap drawing surface. It is suitable for many uses, such as adding graphs to interactive DHTML and drawing game graphics. For a further introduction, see Drawing Graphics with Canvas.

Miscellaneous

Support HTTP/1.1 408 response code

A persistent connection is now correctly closed when a 408 response code (Request timeout) is received. The request is retried in a new connection.

URIs always sent as UTF8

URIs are now always sent to the server as UTF8, regardless of the linking page's encoding. This fixes images and links on sites with non-ASCII filenames.

XForms support

The W3C's XML Forms language allows writing complex forms in XML, and includes features that regular HTML forms do not have, such as client side validation against XML Schema and XML submission/retrieval. Support for XForms comes as an extension, see Mozilla XForms Project Page.