Vertical Mode slick-track height is too high

In the Vertical mode example taken from the repository, the rendered slick-track has a height (2148 px) far in excess of the size of its contents. In my test, the slick-list parent had its height set to 546px - from visual observation at this height the slick-list is just tall enough to contain all 3 sliders.

Why is the nested slick-track div set to a much higher value?

Here is the HTML

```html