failing string opts.key test

My understanding is that `opts = { key: "string" }` will use `key` when deleting / updating in the browser, and will server side add `key="value"` to the dom on the server.

In this test, processing stops after the first row. That is all `r` emits:

```html
<div size="3000000">
size:
<span class="size">
3000000
</span>
</div>
```