I was not face this problem in version 7 but I am facing it in version 8 and version 9.
Below are the snap shots for the screens:
The problem can produced by:
Report Builder → Pick Column
The menu that is appearing, by clicking on Add Column to add new column, the scrolling bar menu appear to select a column, when I click the mouse at the scroll bar to scroll down, the scrolling bar disappear !! So it is not possible to navigate (scrolling down).
I created issue at this link: Pick Column menu in reports is not scrolling down · Issue #11377 · frappe/erpnext · GitHub but umair told me that it is working fine on his machine and it might be my browser problem.
I tried mozilla firefox and chrome and the problem is the same, and I tried firefox from ubuntu and the problem is the same, also I tried to browse from another laptop and it is the same.
I need to know if anyone face this problem and how to recover it (if by upgrading the windows or by change something in browser settings).