Failed to fetch

[StephenBroderick]

TypeError: Failed to fetch 
 While processing action: 
 function (dispatch, getState, api) {
    return api.geth.ext.getBalances(addresses).then(function (balances) {
      dispatch({
        type: _actionTypes2.default.SET_BALANCES,
        accountBalances: addresses.map(function (addr) {
          return { accountId: addr, balance: balances[addr] };
        })
      });

      var tokens = getState().tokens;
      if (!tokens.get('loading')) {
        return dispatch((0, _tokenActions.loadTokensBalances)(addresses));
      }
    });
  }