Dropdowns should have a max-height and a scroll bar

[FelixMalfait]

I was shadowing a client that had created lots of field and the Filter dropdown was bigger than their screen's height. We might (or might not?) want to set a max-height. Also we want to make sure there's a scroll bar upon scroll (when I added a max-height directly in Chrome, the dropdown become scrollable but I couldn't see any scroll bar)

cc @Bonapara for recommandation