Steps to reproduce:

1. Create several filters on the latest data page or the problems page from the Monitoring menu item.
2. You need to create enough filters so that when you click the vertical chevron the vertical list extend beyond the browser window.
3. Notice that the vertical scroll in the browser does not allow you to scroll to the bottom of the list.

I think I found the issue in js/menupopup.js. On line 1784 there is this:

$('.wrapper').append($('<div>', {class: 'menu-popup-overlay'}).append($menu_popup));

The second append is inside the first .append.

.append($menu_popup)

This needs to be fixed to this:

$('.wrapper').append($('<div>', {class: 'menu-popup-overlay'})).append($menu_popup);