Those who use softhddevice in windowed mode can try mouse control in the git test branch.
Uses 3 buttons and a wheel. Double clicking the left button switches to full screen, the right button brings up the menu first and is equivalent to back otherwise. The middle button (wheel) is equivalent to OK. The wheel moves up/down in the menu and controls volume without it. Double clicking in the pip area swaps the pip windows.
The mpv plugin from git test branch can this too.