"Monday, I start work on next-gen web dev tools at Google on the Chrome browser team. Consequently I will no longer be contributing routinely to the development and maintenance of Firebug for Firefox," John J Barton told members of a Firebug mailing list on Sunday.

The change reflects the new rules of the browser market in which Firefox no longer holds such a central place. Firebug was dominant in the days when Mozilla's Firefox was the main challenger of Microsoft's Internet Explorer, but now Chrome is steadily gaining usage share at Firefox's expense.