Firefox Addon to follow links by keyboard?

Solution 1:

Wondering what "hit-a-hint" meant, I ran across HaH. Maybe that does what you call "hit-a-hint"?

Pressing a specified button will activate a HaH-mode (Hit-a-Hint), which means that all "clickable" elements in the area will get a hovering hint over them. This hint has a number, and when that number is entered, the corresponing element is to be "clicked".

Not sure why the screenshot shows letters though, not numbers. Or how it would know that, after pressing a letter like "L", you might, or might not, want to type yet another letter:

Update: Marten found LoL, the successor of the old HaH.

Solution 2:

What about Vim Vixen?

Vim Vixen is a Firefox add-on which allows you to easily navigate the web by keyboard. Since version 57, Firefox has migrated to the WebExtensions API and has dropped support for legacy add-ons. Vim Vixen is a new choice for Vim users since it uses the WebExtensions API.

https://addons.mozilla.org/en-US/firefox/addon/vim-vixen/