How To Add Auto Scroll Bar Vertically To Cssbootstrap Affix Menu For Smaller Screens?

I am using css bootstrap affix plugin as a sticky menu on my site. I have lots of items on the menu which is not an issue on a desktop. However, when I view my site on a small lapt

Solution 1:

I think the problem is that even though you're giving it directive to scroll, there's nothing limiting the height. Try this:

height: 100vh;
overflow-y: scroll;