Currently, the icon of the frame's window just copies the icon of the active tab's first application.
So if you have 2 notepad windows and 1 of them is inside the TaskSpace frame - you'll have just 2 similar windows on the task bar. I suggest to draw taskspace's mini-icon just above the icon of the active tab's active application.
Just to distinguish TaskSpace's windows from normal windows.
Currently, the icon of the frame's window just copies the icon of the active tab's first application. So if you have 2 notepad windows and 1 of them is inside the TaskSpace frame - you'll have just 2 similar windows on the task bar. I suggest to draw taskspace's mini-icon just above the icon of the active tab's active application. Just to distinguish TaskSpace's windows from normal windows.