private void buildExternalsPanel() {

    FormBuilder builder = FormBuilder.create().layout(new FormLayout("fill:pref:grow", "p"));
    int row = 1;
    for (ExternalFileEntry efe : externals) {
      builder.add(efe.getPanel()).xy(1, row);
      builder.appendRows("2dlu, p");
      row += 2;
    }
    builder.add(Box.createVerticalGlue()).xy(1, row);
    builder.appendRows("2dlu, p, 2dlu, p");
    builder.add(addExtPan).xy(1, row + 2);
    builder.add(Box.createVerticalGlue()).xy(1, row + 2);

    // builder.getPanel().setBorder(BorderFactory.createMatteBorder(1,1,1,1,Color.green));
    // externalFilesPanel.setBorder(BorderFactory.createMatteBorder(1,1,1,1,Color.red));
    JScrollPane pane = new JScrollPane(builder.getPanel());
    pane.setBorder(BorderFactory.createEmptyBorder(5, 5, 5, 5));
    externalFilesPanel.setMinimumSize(new Dimension(400, 400));
    externalFilesPanel.setPreferredSize(new Dimension(400, 400));
    externalFilesPanel.removeAll();
    externalFilesPanel.add(pane, BorderLayout.CENTER);
    externalFilesPanel.revalidate();
    externalFilesPanel.repaint();
  }