Don't open multiple topics about this. I merged those 2 topics.
From that src/interface/inp_keys.h file it's using, this source code is over 13 years old, assuming it's even our source code, which i highly doubt since the code back then had a different define for FBK_PREVTRACK.
So basically it's a hard fork of an extremely old version of the fbalpha source code.
We only support our source code, and preferably the current one, i'm locking, don't bring up this non-sense again.