I'm assuming the behavior you are requesting is to be able to minimize/restore the floating window independently of the main GUI, so that you could choose to minimize the main GUI while keeping the floating window open. If that could be done, I'm fine with it, but the previous attempt was a total fail for the reasons described in the topic you linked in your last post.
I mentioned in that topic, "The desired behavior would be that the floating window stays open until deliberately minimized, no matter what is done elsewhere in MusicBee. That is the concept of being de-linked it would seem to me"---if that could be successfully accomplished without causing the floating window to auto-hide behind the main open GUI at any action, this would also give you the option of working with the floating window open while the main GUI is minimized. In which case, +1 to your request.