While reading the code of flutter apps, I’ve seen this particular piece of code repeated way too many times: returnMaterialApp(theme:ThemeData.dark().copyWith(textTheme:...),home:...) This is problematic for a couple reasons that become clear when we take a peek at how ThemeData works. This is taken directly from the material library’s code: factoryThemeData.dark()=>ThemeData(brightness:Brightness.dark); That is all that it does. It just changes the brightness parameter from light to dark...