Unreachable content because page scrool bar is missing

Webix JS
1

I have quite a long page of many rows and end up with some of them unreachable. See: http://webix.com/snippet/fac93a95
On a monitor with resoltion 1920x1080 nothing below line 50 can be seen
Why does this happen and how can i prevent it?

Thanks in advance!

2

You can place the main ui in the scrollview

http://webix.com/snippet/fac93a95

3

By the way, it is possible to restore the page scroll through css