docs: private void setupLookAndFeel() {
          if (lookAndFeelSet) {
              return;
          }
          lookAndFeelSet = true;
  
          if (setLookAndFeel(System.getProperty("swing.defaultlaf"))) {
              return;
          }
  
          OptionsParam options = Model.getSingleton().getOptionsParam();
  
          if (setLookAndFeel(getLookAndFeelClassname(options.getViewParam().getLookAndFeel()))) {
              return;
          }
  
          if (Constant.isMacOsX()) {
              OsXGui.setup();
          } else if (setLookAndFeel(getLookAndFeelClassname("Nimbus"))) {
              return;
          }
  
          setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
      }