The Opera client used to be universally recognized as the alternative browser to Internet Explorer, and then along came Firefox and stole all the alternative browser thunder - and how. But the fat lady is still singing, and to prove it has released the Opera Dragonfly to debug web pages, widgets and web applications on any device.

Available in Opera 9.5 beta 2 to start with, the alpha release of Dragonfly includes a JavaScript Debugger, DOM and CSS Inspectors, Error Console and Command Line.

The full list of Dragonfly features is as follows:

  • Debug pages whether they are on your computer or a separate, supported device. Opera Dragonfly can remotely connect to computers and devices running a supported version of Opera.
  • Opera Dragonfly is a new breed of hybrid application: part desktop application, part Web application. It resides in local persistent storage without any server-side processing, yet instantly updates when a new version is released - just like your favorite Web sites.
  • Opera Dragonfly's source code is released under the BSD license, making the code itself available for inspection and reuse.
  • View source isn't much use if you use DOM Scripting to alter the DOM. Opera Dragonfly allows you to inspect the updated DOM and all its properties. Support for editing the DOM will follow.
  • Check out what CSS rules apply to which element, and what rules are inherited or set by browser defaults. Overridden rules are highlighted so you can see what styles are or aren't applied. Support for editing CSS rules will follow.
  • Opera Dragonfly's full-featured JavaScript debugger enhances user ability to build sophisticated Ajax applications. Step through your code line by line, setting break points along the way. This allows you to make sure your application and scripts are acting as you designed them.
  • An advanced error console allows you to see, filter and log any errors in your scripts, pointing to the exact position the error occurred. Use this in combination with the other tools to hunt down and fix your site's bugs.

Christen Krogh, Chief Development Officer, Opera Software says "At Opera we've always believed there should only be One Web, accessible from any device. This One Web must be built on open Web standards, enabling the same degree of innovation to happen on mobile and devices as on desktop. With Opera Dragonfly we take an important step toward our vision by providing Web developers with the tools to unify both development and experiences across devices."