useDApp: useEtherBalance returns undefined

Following the basic example:

export function App() {
  const { activateBrowserWallet, deactivate, account } = useEthers()
  const userBalance = useEtherBalance(account)


  return (
    <div>
      {!account && <button onClick={activateBrowserWallet}> Connect </button>}
      {account && <button onClick={deactivate}> Disconnect </button>}

      {account && <p>Account: {account}</p>}
      {userBalance && <p>Ether balance: {formatEther(userBalance)} ETH </p>}
    </div>
  )
}

I can get my account address, but I get undefined for userBalance, no matter what I do it is always undefined.