docs: protected List<String> getIgnoredProperties() {
  
          if (m_ignoredProperties == null) {
              // get list of ignored properties
              m_ignoredProperties = OpenCms.getImportExportManager().getIgnoredProperties();
              if (m_ignoredProperties == null) {
                  m_ignoredProperties = Collections.emptyList();
              }
          }
          return m_ignoredProperties;
      }