"Dragonflies eat bugs, and that is exactly what we want [Dragonfly] to do for developers around the world," said David Storey, an Opera developer relationship manager, in a statement.

is not the first browser-based debugger. Mozilla, for example, offers Firebug, and Google's Chrome browser also features some built-in element inspection features as well. Dragonfly also offers the ability to debug Web pages on smartphones, televisions and other devices, by hooking them up to the developer's PC.

In open-source development for nearly five years, Dragonfly was designed to help Web page designers grapple with increasingly complex Web pages and Web applications.

"We were coming into an age where JavaScript was becoming popular again, and Ajax was the buzzword on everyone's lips. Creating complex Web applications without such tools made it hard to support Opera on those services," Storey said, on the Opera site.