2 monitors with different aspect ratios causing issues with UI

I have had this problem solved before, but I replaced my computer recently, and I can't recall how I solved it

I have a laptop with a 16:10 aspect ratio (Dell XPS 9710), and I use a secondary pen display with an aspect ration of 16:9 (Cintiq Pro 24"), all drivers and programs are current.

When I move iIlustrator to my 2nd monitor, and try to adjust font type (for example), the scrollbar in the font mrenu is hidden, which makes trying out new fonts very difficult.

I know there is a very simple setting in illustrator that fixes this, but I can't recall what it is ...