R vertical scroll not working
<p>I am trying to get a vertical scroll but this isn't working, can anybody explain why?  I would also like to default to show 20 rows at once.</p>

<p>Thanks </p>

<hr>

<pre><code>title: "Untitled"
output: 
  flexdashboard::flex_dashboard:
    orientation: columns
    vertical_layout: fill
---

```{r setup, include=FALSE}
library(flexdashboard)
library(DT)
```

Column {data-width=650}
-----------------------------------------------------------------------

### Chart A

```{r}
datatable(cars ,options = list(c(bPaginate = F, scrollY=T)),  filter = 'top')
```
</code></pre>