During init, query screen for _NET_ACTIVE_WINDOW and set that client as

active; while we already look at what's under the pointer, use this
information first, then look under the pointer (saving that round-trip).
This restores the active state to a client after restart even if the
pointer is not above it (and of course the pointer is not above another
client).

xutil.c

@@ -256,6 +256,22 @@ xu_ewmh_net_active_window(struct screen_ctx *sc, Window w)
 	    XA_WINDOW, 32, PropModeReplace, (unsigned char *)&w, 1);
 }
 
+Window
+xu_ewmh_get_net_active_window(struct screen_ctx *sc)
+{
+	long		*p;
+	Window		 win;
+
+	if ((xu_getprop(sc->rootwin, ewmh[_NET_ACTIVE_WINDOW],
+	    XA_WINDOW, 32, (unsigned char **)&p)) <= 0)
+		return(None);
+
+	win = (Window)*p;
+	XFree(p);
+
+	return(win);
+}
+
 void
 xu_ewmh_net_wm_desktop_viewport(struct screen_ctx *sc)
 {