Chrome's engine works fine for me and I use much more JS than most people. The only complaint I have is the minimal error output compared to Firebug's debugging capabilities.
JavaScript: IP.Chat-Specific Theme 1.1.3
// requested by BlueWyvern4
Adds the ability to use a specific theme for IP.Chat separate from the forum theme. The theme can be changed while in IP.Chat via a separate menu next to the default theme changer.
Images:
How to Install
Is it what you wanted?
Fixed the link. Nice catch.