This snippet here: .then(         response => response.json(),         // Do not use catch, because that will also catch         // any errors in the dispatch and resulting render,         // causing a loop of 'Unexpected batch number' errors.         // https://github.com/facebook/react/issues/6895         error => console.log('An error occurred.', error)       ) I understand the warning not to use .catch(fn) , since it swallows exceptions, but .then(_, fn) , as used above, also swallows the exception.