The current version is 0.5.5.
Download the installer, guaranteed spyware/malware free and packaged with a straightforward and complete un-installer.
To be able to use Companion.JS you'll need to have a Microsoft script debugger installed. There are many cases where you already have this component install. To check if you need it see Installing Companion.JS for details.
Here are some screenshots :
Detailled Error reporting
In the top-left corner the notifying panel which pops-up when an error occurs in the current page if the Companion.JS panel is not open. At the bottom of the page...
Console API feature