On X11, this is done by inspecting the _NET_ACTIVE_WINDOW property
on the root window, as described in the
Extended Window Manager Hints.
If there is no currently currently active
window, or the window manager does not support the
_NET_ACTIVE_WINDOW hint, this function returns NULL.
On other platforms, this function may return NULL, depending on whether
it is implementable on that platform.
The returned window should be unrefed using g_object_unref() when
no longer needed.
Returns the screen’s currently active window.
On X11, this is done by inspecting the _NET_ACTIVE_WINDOW property on the root window, as described in the Extended Window Manager Hints. If there is no currently currently active window, or the window manager does not support the _NET_ACTIVE_WINDOW hint, this function returns NULL.
On other platforms, this function may return NULL, depending on whether it is implementable on that platform.
The returned window should be unrefed using g_object_unref() when no longer needed.