static Border getBorder(boolean undecoratedWindow) {
        Border result = UIManager.getBorder("Window.border");
        if (result == null && undecoratedWindow &&
            SystemInfo.isUnix && !SystemInfo.isMac && Registry.is("ide.linux.use.undecorated.border")) {
          result = UIManager.getBorder("Window.undecorated.border");
        }
        return result;
      }
static Border getBorder(boolean undecoratedWindow)