docs: public String getVfsName(CmsObject cms, String rfsName) {
  
          CmsStaticExportData data = getRfsExportData(cms, rfsName);
          if (data != null) {
              String result = data.getVfsName();
              if ((result != null) && result.startsWith(cms.getRequestContext().getSiteRoot())) {
                  result = result.substring(cms.getRequestContext().getSiteRoot().length());
              }
              return result;
          }
          return null;
      }