docs: protected List<HistoryReference> getSelectedHistoryReferences(HttpMessageContainer httpMessageContainer) {
          if (httpMessageContainer instanceof SelectableHistoryReferencesContainer) {
              return ((SelectableHistoryReferencesContainer) httpMessageContainer).getSelectedHistoryReferences();
          } else if (httpMessageContainer instanceof SingleHistoryReferenceContainer) {
              SingleHistoryReferenceContainer singleContainer = (SingleHistoryReferenceContainer) httpMessageContainer;
              if (!singleContainer.isEmpty()) {
                  List<HistoryReference> selectedHistoryReferences = new ArrayList<>(1);
                  selectedHistoryReferences.add(singleContainer.getHistoryReference());
                  return selectedHistoryReferences;
              }
          }
  
          return Collections.emptyList();
      }