Here I got stuck on where it is defined.
I found a reference on window.Ffclientconfig inside
FFChat2/ff-chat-1.2-min.js
but not where it is defined.
A second "undefined" object problem happened: n[o.osName] is undefined
Thanks to Steve for this really really beautiful javascript by the way - it was a pleasure to read through it, well structured, very great work! Let's get that one running!