Do you have Compiz Fusion enabled? If yes, then install Compiz Config Settings Manager(or not if it is already installed)- in terminal write: sudo apt-get install ccsm Then open it (press Alt+F2, write ccsm). In general options disable "Hide skip taskbar windows" option.
Do you have Compiz Fusion enabled? If yes, then install Compiz Config Settings Manager(or not if it is already installed)- in terminal write: sudo apt-get install ccsm Then open it (press Alt+F2, write ccsm). In general options disable "Hide skip taskbar windows" option.