Scrolling a CSS-driven dropdown menu and overflow:hidden?

default elements in html that are tabbable are:

<a> , <area> , <button> , <input> , <object> , <select> , and <textarea>

If someone were to “plop” my code for drop-down menus, my tabbable elements are my li.

What I wish to do is select a non- TAB key to traverse my li, thus keeping the TAB key reserved by HTML

FWIW, I just let my selection of the TAB key ride … eventually it gets to my last li and then tabs to your <a> or <input> html and then proceeds to the Browser’s tabbable stuff and cycles back to the beginning of my li items.

Not too awful I guess?

Suggestions appreciated