New version of NetBeans has been released on 20 November 2008. The installation parallel to the old version 6.0 went off completely troublefree.
The new JavaScript Debugger will be activated as follows:
During the first Debug call of a project the Firefox extensions Firebug and NetBeans Firefox Extension will be installed.
To debug a JavaScript file inside Firefox choose menu item "Script" in the Firebug view. After that switch from HTML file to an special JavaScript file by click on the file name inside the top menu bar and set the breakpoints.
To debug a JavaScript file inside the NetBeans IDE insert the keyword debugger;.
[1] NetBeans 6.5