public static @NotNull JComponent wrapRootPaneNorthSide(@NotNull JRootPane rootPane, @NotNull JComponent northComponent) {
    if (isVersion2()) {
      return MacWinTabsHandlerV2._wrapRootPaneNorthSide(rootPane, northComponent);
    }

    JPanel panel = new NonOpaquePanel(new BorderLayout());

    JPanel filler = new OpaquePanel();
    filler.setBorder(JBUI.Borders.customLineBottom(UIUtil.getTooltipSeparatorColor()));
    filler.setVisible(false);

    panel.add(filler, BorderLayout.NORTH);
    panel.add(northComponent);
    rootPane.putClientProperty(WIN_TAB_FILLER, filler);
    rootPane.putClientProperty("Window.transparentTitleBarHeight", 28);
    return panel;
  }
public static @NotNull JComponent wrapRootPaneNorthSide(@NotNull JRootPane rootPane, @NotNull JComponent northComponent)