1. When I choose another language than the system default one and close the window, the chosen language will be immediately used - good. But when I choose "system default" (back), it will be used after app restart only - bad.
2. Imagine I have just opened the menu, chose another language (important!) and closed the window (not the whole app). When I now return back to the menu, the items "Voice engine" and "Voice language" will load quite a long time (I am using TTS). During that loading time, I cannot switch "Application language", as the app does not react, leaving the user puzzled.