Boss Button
 

I've searched google for half an hour for a location of this boss button. No luck.
Maybe i'm just blind or something but really can't find this Boss Button on BSplayer.
I'm using Base Skin.
Maybe someone will help me to locate that magic button.

rightclick > Options > Preferences *) > Key definitions & WinLIRC
There you can define (separately for [Windowed mode] and [Full screen mode]) which key is to be 'Boss button' (for both modes defaultkey is [F10]) as well as define on (3rd) Tab ['Boss' button configuration] what it must do for you.
:wink:
*): Base skin has a Preferences button so that you can go here directly