What’s new in Aurora 6?

The most notable addition to this new Aurora are the <progress> element, window.matchMedia API, better APIs for binary data, Server-Sent Events as well as the return of WebSockets.

Aurora 6 has been published last week and can be downloaded from firefox.com/channel.

The <progress> element

This element can be used to give a visual cue of something in progress in the page. System progress bars are being used, which means that users of MacOS and Linux will see something different than what is pictured here.

matchMedia

window.matchMedia() is the javascript equivalent of CSS Media Queries.

Binary data APIs improvements

• XHR2 responseType and response attributes allow getting the response from an XHR in the form of efficient Blob or ArrayBuffer.
• FileReader.readAsArrayBuffer() allow reading files and get the response as an ArrayBuffer.
• BlobBuilder allow concatenating multiple blobs as well as text and ArrayBuffer into a single Blob.

Expect to see even more improvements in this area in Aurora 7.

Server Sent Events

Server Sent Events are a mean for a server-side script to generate client-side events accompanied with data.

Messages generated on the server-side with a text/event-stream mime-type and consist of a list of events data.

data: data generated by the server

data: this line will generate a second event

WebSockets are back!

WebSockets can be used to create an interactive communication channel between a browser and a server. They are already used to build “HTML5” chats, multiplayer games, and much much more.
Note that this API will be temporarily namespaced in prevision of upcoming changes to the specification.

Other Interesting Additions

• DOM
  • the element.dataset property can be used to access/modify “data-” prefixed attributes of HTML elements
  • window.postMessage generate a structured clone, which means that it is now compatible with objects that used to be serialized to JSON strings
  • DOM3 CustomEvent specification has been implemented
  • events now have an defaultPrevented property indicating whether the event.preventDefault() method has been called
  • the onhashchange event now has newURL and oldURL properties
  • beforeprint and afterprint events have been implemented
• JavaScript
  • with WeakMap, developers can start playing with weak reference in javascript
  • setTimeout and setInterval delays are now higher in inactive tabs
• CSS
  • text-decoration is now more customizable thanks to -moz-text-decoration-color, -moz-text-decoration-line and -moz-text-decoration-style properties
  • -moz-hyphens controls how hyphenation of words during line wrapping is handled
• Network
  • Accelerated Connection Retry for HTTP
• Tools
  • Improvements to the Web Console
  • Improvements to the about:memory page
• Plugins
  • Adobe Flash Cookies (LSOs) are now cleared when clearing cookies

Learn about what’s new in Aurora 6’s user interface on blog.mozilla.com/futurereleases and let us know what you think.