Horizontal scroll disappear when adding extra div

Gantt
#1

Hi all,

When I add a div before the gantt_here div, the horizontal scroll disappear:

buttons

But if I put the div after the gantt_here div, the scroll exist:

buttons

Why is that?

Thanks in advance

#2

Hi again,

OK so the height:100% places the scroll outside of the browser when adding a div above…
Can I have both 100% and div above or shall I just set the height to like 98% ?

Regards