message: Fix key backup status when missing device
  We might not have the device in `sig.device`, so we have to check for it's
  existence first. This fixes the "Unable to load key backup status" message that
  is incorrectly triggering.
  Fixes
diff: @@ -221,7 +221,10 @@ export default class KeyBackupPanel extends React.PureComponent {
  {sub}
  </span>;
  const device = sub => <span className="mx_KeyBackupPanel_deviceName">{deviceName}</span>;
  - const fromThisDevice = sig.device.getFingerprint() === MatrixClientPeg.get().getDeviceEd25519Key();
  + const fromThisDevice = (
  + sig.device &&
  + sig.device.getFingerprint() === MatrixClientPeg.get().getDeviceEd25519Key()
  + );
  let sigStatus;
  if (!sig.device) {
  sigStatus = _t(
  