[KevinH]

Eclpise+JSEclipse for editing.

Firefox as your browser.
Venkman for a debugger.
http://www.mozilla.org/projects/venkman/
https://addons.mozilla.org/extension...nfo.php?id=216
http://getahead.ltd.uk/ajax/venkman (FF 1.5 build)

Console2 is also nice for better error reporting/filtering.
http://forums.mozillazine.org/viewtopic.php?t=318102