Program: 20707
Project: 20707
Buggy source:
private void initConfigGui(){
  try {
    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
  }
 catch (  Exception e1) {
    e1.printStackTrace();
  }
  final DefaultListModel listModel=new DefaultListModel();
  for (  String folder : folderlist) {
    listModel.addElement(folder);
  }
  final JList list=new JList(listModel);
  list.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
  final JDFileChooser filechooser=new JDFileChooser();
  filechooser.setFileSelectionMode(JDFileChooser.DIRECTORIES_ONLY);
  filechooser.setMultiSelectionEnabled(true);
  config.setGroup(new ConfigGroup(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),getIconKey()));
  JButton addButton=new JButton(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"));
  addButton.setIcon(JDTheme.II("String_Node_Str",16,16));
  addButton.addActionListener(new ActionListener(){
    public void actionPerformed(    ActionEvent e){
      filechooser.showOpenDialog(null);
      for (      File file : filechooser.getSelectedFiles()) {
        folderlist.add(file.getAbsolutePath());
        listModel.addElement(file.getAbsolutePath());
        folderlistHasChanged=true;
      }
    }
  }
);
  JButton removeButton=new JButton(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"));
  removeButton.setIcon(JDTheme.II("String_Node_Str",16,16));
  removeButton.addActionListener(new ActionListener(){
    public void actionPerformed(    ActionEvent e){
      while (!list.isSelectionEmpty()) {
        folderlist.remove(list.getSelectedIndex());
        listModel.remove(list.getSelectedIndex());
        folderlistHasChanged=true;
      }
    }
  }
);
  JPanel p=new JPanel(new MigLayout("String_Node_Str","String_Node_Str"));
  p.add(addButton,"String_Node_Str");
  p.add(removeButton,"String_Node_Str");
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_COMPONENT,new JScrollPane(list),"String_Node_Str"));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_COMPONENT,p,"String_Node_Str"));
  config.setGroup(new ConfigGroup(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),getIconKey()));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_BUTTON,new ActionListener(){
    public void actionPerformed(    ActionEvent e){
      String folder=(String)list.getSelectedValue();
      if (folder != null)       openInFilebrowser(folder);
    }
  }
,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDTheme.II("String_Node_Str",16,16)));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_BUTTON,new ActionListener(){
    public void actionPerformed(    ActionEvent e){
      if (JDFlags.hasSomeFlags(UserIO.getInstance().requestConfirmDialog(UserIO.NO_COUNTDOWN,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")),UserIO.RETURN_OK)) {
        String folder=(String)list.getSelectedValue();
        if (folder != null)         emptyFolder(folder);
      }
    }
  }
,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDTheme.II("String_Node_Str",16,16)));
  config.setGroup(new ConfigGroup(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),getIconKey()));
  if (OSDetector.isWindows()) {
    config.addEntry(new ConfigEntry(ConfigContainer.TYPE_CHECKBOX,subConfig,FolderWatchConstants.PROPERTY_OPTION_RECURSIVE,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")).setDefaultValue(false));
  }
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_CHECKBOX,subConfig,FolderWatchConstants.PROPERTY_OPTION_IMPORT,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")).setDefaultValue(true));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_CHECKBOX,subConfig,FolderWatchConstants.PROPERTY_OPTION_IMPORT_DELETE,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")).setDefaultValue(false));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_CHECKBOX,subConfig,FolderWatchConstants.PROPERTY_OPTION_HISTORY,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")).setDefaultValue(true));
}

Fixed version (ground truth):
private void initConfigGui(){
  try {
    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
  }
 catch (  Exception e1) {
    e1.printStackTrace();
  }
  final JDFileChooser filechooser=new JDFileChooser();
  filechooser.setFileSelectionMode(JDFileChooser.DIRECTORIES_ONLY);
  filechooser.setMultiSelectionEnabled(true);
  final DefaultListModel listModel=new DefaultListModel();
  final JList list=new JList(listModel);
  list.setSelectionMode(ListSelectionModel.MULTIPLE_INTERVAL_SELECTION);
  for (  String folder : folderlist)   addListModelEntry(list,folder);
  config.setGroup(new ConfigGroup(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),getIconKey()));
  JButton addButton=new JButton(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"));
  addButton.setIcon(JDTheme.II("String_Node_Str",16,16));
  addButton.addActionListener(new ActionListener(){
    public void actionPerformed(    ActionEvent e){
      filechooser.showOpenDialog(null);
      for (      File file : filechooser.getSelectedFiles()) {
        if (!folderlist.contains(file.getAbsolutePath())) {
          folderlist.add(file.getAbsolutePath());
          addListModelEntry(list,file.getAbsolutePath());
          folderlistHasChanged=true;
        }
      }
    }
  }
);
  JButton removeButton=new JButton(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"));
  removeButton.setIcon(JDTheme.II("String_Node_Str",16,16));
  removeButton.addActionListener(new ActionListener(){
    public void actionPerformed(    ActionEvent e){
      while (!list.isSelectionEmpty()) {
        folderlist.remove(list.getSelectedIndex());
        listModel.remove(list.getSelectedIndex());
        folderlistHasChanged=true;
      }
    }
  }
);
  JPanel p=new JPanel(new MigLayout("String_Node_Str","String_Node_Str"));
  p.add(addButton,"String_Node_Str");
  p.add(removeButton,"String_Node_Str");
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_COMPONENT,new JScrollPane(list),"String_Node_Str"));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_COMPONENT,p,"String_Node_Str"));
  config.setGroup(new ConfigGroup(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),getIconKey()));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_BUTTON,new ActionListener(){
    public void actionPerformed(    ActionEvent e){
      if (!list.isSelectionEmpty()) {
        String folder=folderlist.get(list.getSelectedIndex());
        openInFilebrowser(folder);
      }
    }
  }
,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDTheme.II("String_Node_Str",16,16)));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_BUTTON,new ActionListener(){
    public void actionPerformed(    ActionEvent e){
      if (!list.isSelectionEmpty()) {
        if (JDFlags.hasSomeFlags(UserIO.getInstance().requestConfirmDialog(UserIO.NO_COUNTDOWN,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")),UserIO.RETURN_OK)) {
          String folder=folderlist.get(list.getSelectedIndex());
          emptyFolder(folder);
          updateSelectedListEntry(list);
        }
      }
    }
  }
,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDTheme.II("String_Node_Str",16,16)));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_BUTTON,new ActionListener(){
    public void actionPerformed(    ActionEvent e){
      showGui();
    }
  }
,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),JDTheme.II("String_Node_Str",16,16)));
  config.setGroup(new ConfigGroup(JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str"),getIconKey()));
  if (OSDetector.isWindows()) {
    config.addEntry(new ConfigEntry(ConfigContainer.TYPE_CHECKBOX,subConfig,FolderWatchConstants.PROPERTY_OPTION_RECURSIVE,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")).setDefaultValue(false));
  }
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_CHECKBOX,subConfig,FolderWatchConstants.PROPERTY_OPTION_IMPORT,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")).setDefaultValue(true));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_CHECKBOX,subConfig,FolderWatchConstants.PROPERTY_OPTION_IMPORT_DELETE,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")).setDefaultValue(false));
  config.addEntry(new ConfigEntry(ConfigContainer.TYPE_CHECKBOX,subConfig,FolderWatchConstants.PROPERTY_OPTION_HISTORY,JDL.L(JDL_PREFIX + "String_Node_Str","String_Node_Str")).setDefaultValue(true));
}