Companion.JS (pronounced Companion dot JS or CJS) is a Javascript debugger for IE. The current version is 0.4.1.
Companion.JS adds the following features to IE :
Detailled javascript error reporting (call stack and real file name where the error occured).
"Firebug"-like Console API feature.
Javascript console feature useful to inspect javascript objects at runtime.
A toolbar icon to open the Companion.JS panel.