Was getting an error: "Cannot find a library instance of LibSink-2.0" for one of my chars, but fine on the others. I'm not sure why this happens on this particular character as I run with no externals - therefore all libraries are checkboxed for every char regardless if that char uses addons or not, and all of them use Witchhunt.
Perhaps JWoWUpdater messed up and removed LibSink1.0? Or a certain addon on other characters loaded LibSink-2.0 making Witchhunt work correctly? (Thus no need for version 1)
I had to fix by downloading LibSink-1.0 and putting it alongside version 2 in my Interface folder.
edit: Looking at my daily addon backups, LibSink-1.0 never existed. So one of the new addon/lib updates recently has probably messed up Witchhunt.