code: public Map<String, String> getParams() {
  
          Map<String, String> params = new HashMap<>(1);
          params.put(PARAM_COLLAPSED, Boolean.TRUE.toString());
          return params;
      }
docs: Add the option specifying if the categories should be displayed collapsed
  when the dialog opens.
  
  @see org.opencms.ui.actions.I_CmsADEAction#getParams()