`startSyncing` does not allow to save wallet until sync completes
If I install a listener for wallet sync and try to save the wallet periodically while it syncing (so that the sync process is not lost between browser page reloads) the call to `save` hangs indefinitely.

The very slow workaround here is to do:
```
            await wallet.stopSyncing();
            await wallet.save();
            await wallet.startSyncing(15000);
```