docs: function handleQueryError (err) {
  
          queryErrorCount++;
  
          // Something has gone terribly wrong. Break from loop.
          if (queryErrorCount > 1) {
  
              // Reset all filters.
              session.list.formData = {};
  
              // Notify the user that an error has occured.
              req.linz.notifications.push(linz.api.views.notification({
                  text: 'One of the filters is repeatedly generating an error. All filters have been removed.',
                  type: 'error'
              }));
  
              // Rerun the query at the last known working state.
              // eslint-disable-next-line no-use-before-define
              return getModelIndex();
  
          }
  
          // Reset the last known working state.
          session.list.formData = session.list.previous.formData;
  
          // If we're in development mode, return the error
          // so that the developers are aware of it and can fix it.
          if (isDevelopment) {
              return next(err);
          }
  
          // Notify the user that an error has occured.
          req.linz.notifications.push(linz.api.views.notification({
              text: 'An error has occured with one of the filters you added. It has been removed.',
              type: 'error'
          }));
  
          // Rerun the query at the last known working state.
          // eslint-disable-next-line no-use-before-define
          return getModelIndex();
  
      }