Firebug 2.0 Web dev tool steps up debugging

Version 2.0 of the popular open source Firebug Web development tool, released this week, features a slew of programming improvements including debugging enhancements, syntax highlighting, and better code auto-completion.

The debugger is the heart of Firebug 2.0 and its features are integrated throughout the tool, Firebug team leader Jan Odvarko said. "Firebug's debugger is now based on new debugging APIs -- known also as JSD2 -- that are more stable, faster, and consume less memory."

The tool's Script panel supports syntax highlighting, and Syntax coloring is also offered for HTML and the CSS source edit mode. Code auto-completion, which works for HTML, HTML style, and SVG attributes, is now available in the Command Editor within the console panel.

For DOM events inspection, version 2.0 offers an Events side panel listing event handlers on the page, grouped by event type for the selected DOM element. Developers can find out which HTML event is associated with a specific event listener or see JavaScript source code. The Search function in the HTML panel has been improved, and the Script panel supports a pretty print capability for reformatting source code -- a helpful feature when dealing with minified JavaScript code.

The JavaScript expressions inspector in Firebug 2.0 enables inspection of JavaScript expression details, and developers can group console logs coming in a row from the same panel. Original CSS color values can be displayed in the CSS panel, making it easier to compare styles interpreted by the browser with ones in the original CSS source file. Developers also can modify return values of a JavaScript function.

Firebug's builders collected feedback from developers and designers and used the feedback to tweak features in this release. "Firebug's strength is mainly its user interface and user experience. It's simple and intuitive, a handy tool," said Odvarko. "Other built-in tools introduced in, [for example,] Firefox, Chrome, and IE (Internet Explorer) might have more features now, but the user experience of those individual features is often [a] step behind Firebug."

Introduced in 2006, Firebug has been downloaded 70 million times. It's compatible with the Firefox browser and is registered as a Mozilla trademark and maintained by a group of developers around the world. Version 2.0 is downloadable at the Firebug website.