@WINMONITOR — Searches for a matching window, and returns the monitor on which it appears.

Syntax:
%@WINMONITOR[window,flags]

windowwindow title, program name, PID, or HWND
flagsbitmapped:
    1: return a monitor name; otherwise it’s a monitor number

@WINMONITOR returns a monitor index: 1 for the first monitor, 2 for the second, and so on. If no matching window was found, or if the window does not overlap any display monitor, @WINMONITOR returns 0.