FireBug 0.4 includes JavaScript Debugger

Web developers need no longer deal with the flakiness of Venkman, Mozilla’s venerable but stagnant JavaScript debugger.

With the release of FireBug 0.4, an excellent extension for analyzing JavaScript and CSS errors and XMLHttpRequest operations (AJAX) that we have covered before, Firefox now has a powerful, up-to-date debugger that you don’t need to hack to get working.

Firebug Debugger screenshot

In addition to standard debugging capabilities like setting breakpoints, stepping through code, and inspecting variables, FireBug adds support for checking assertions, automatic breaking on JavaScript errors, and more.

If you do any JavaScript work at all, grab FireBug now and consider making a donation to developer Joe Hewitt, who built the thing in his spare time.