Opera 11 alpha out: developers, start your extension engines

Last week, Opera announced that it was working on version 11 of its desktop browser and hinted that it would share an early version soon. Today, the company released Opera 11 alpha for Windows, Mac, and Linux to the public.

Version 11 comes with a new version of Opera's layout engine. Presto 2.6.37 improves performance while also adding hundreds of bug fixes and enhanced Web standards support as well as support for Websockets. There's also a new installer for Windows that Opera claims makes the installation/upgrade process twice as fast, with a 10 percent smaller download size.

The biggest new feature is easily Opera Extensions. Unlike Opera Widgets and Opera Unite applications, extensions allow adding features and functionality directly into the browser itself; some extensions have interface elements while others can run exclusively in the background.

Developers can create extensions using open standards such as HTML5, CSS, JavaScript, and supported APIs (the alpha release supports injectable JavaScript, callouts, certain UI items, plus a basic Tabs and Windows API). Extensions are based on the W3C Widget specification, which is being considered for an Open Standard effort. The company is also trying to make it easy to port extensions from certain browsers, which it says will only require "a few tweaks" to the code.

To create an extension, read the tutorials and "getting started" guide, develop the code, and upload it to the Opera extensions webpage. Opera says it will check all extensions for defects and malicious software before they are made public.

The addition of extensions marks an important milestone for Opera. The company has always insisted on including features right in the browser, arguing that Opera included everything important you could get out of extensions without any extra installation ("the most powerful browser out-of-the-box").

At the start of the year, Google added extension support to Chrome in version 4. Apple just added extension support this past summer in version 5 while Firefox has had them for years. If you can't beat 'em, join 'em.