Merge branch 'master' into jgrpp

# Conflicts:
#	src/blitter/32bpp_anim.cpp
#	src/rail_gui.cpp
#	src/saveload/saveload.cpp
#	src/train_cmd.cpp
#	src/vehicle_base.h

src/window.cpp

@@ -3051,6 +3051,10 @@ void UpdateWindows()
 		w->ProcessHighlightedInvalidations();
 	}
 
+	/* Skip the actual drawing on dedicated servers without screen.
+	 * But still empty the invalidation queues above. */
+	if (_network_dedicated) return;
+
 	static int we4_timer = 0;
 	int t = we4_timer + 1;