When one sends two continous message, First message may disappear

It would not show first message, But it is sent. And when you move to another thread and back to it. You can see it then.

I think the first message has not yet hit the server while second one has been sent.

```
Client: 4.4.1-20190910185008+b5f8897c2a
Service: 4.4.1-20190910185008+b5f8897c2a
```

Start by reproducing the issue with two consecutive messages using the listed Client and Service versions, then move to another thread and return to confirm the first message appears. Done means both sent messages remain visible immediately without switching threads; the payload names no files or tests to inspect.

Written by the indexing model from the issue text.