fixId() {

    const meta = this.wiki.getTiddlerData(env.ref.sysMeta, {});

    this.executeUpgrade('0.9.2', meta.dataStructureState, () => {

      if (utils.isLeftVersionGreater('0.9.2', meta.originalVersion)) {
        // path of the user conf at least in 0.9.2
        const userConf = '$:/plugins/felixhayashi/tiddlymap/config/sys/user';
        const nodeIdField = utils.getEntry(userConf, 'field.nodeId', 'tmap.id');
        utils.moveFieldValues(nodeIdField, 'tmap.id', true, false);
      }
    });

  }
Special fix that is not invoked along with the other fixes but
when creating the index (see caretaker code).

Changes:
1. The node id field is moved to tmap.id if **original version**
   is below v0.9.2.