NotificationManager -> Separate notification update from its render to reduce the amount of scene refresh

src/libslic3r/Technologies.hpp

@@ -89,6 +89,7 @@
 #define ENABLE_2_3_0_BETA2 1
 
 #define ENABLE_ARROW_KEYS_WITH_SLIDERS (1 && ENABLE_2_3_0_BETA2) 
+#define ENABLE_NEW_NOTIFICATIONS_FADE_OUT (1 && ENABLE_2_3_0_BETA2) 
 
 
 #endif // _prusaslicer_technologies_h_