Opera Dragonfly debugs webpages on the fly

Opera announced the inclusion of Opera Dragonfly in Opera 9.5 beta 2. This developer tool is designed to debug web pages, widgets and web applications on any device. Today's alpha release will upgrade automatically and includes a JavaScript Debugger, DOM and CSS Inspectors, Error Console and Command Line. Opera 9.5 beta 2 can be downloaded over here.

"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," says Christen Krogh, Chief Development Officer, Opera Software. "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."

Features in Opera Dragonfly alpha include:

Remote debug
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.

Auto update
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.

Open and free
Opera Dragonfly's source code is released under the BSD license, making the code itself available for inspection and reuse.

DOM Inspector
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.

CSS Inspector
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.

JavaScript Debugger
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.

Error Console and Command Line
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.