Vimium-FF [0] works just fine and has since I first installed FF57 Developer Edition (right after FF55 came out?)
[0]: https://addons.mozilla.org/en-US/firefox/addon/vimium-ff/
[0]: https://addons.mozilla.org/en-US/firefox/addon/vimium-ff/
.. works just fine ...
Not really. You can't yank the url (yy) in Firefox, and the search is borked sometimes when there is no match on the page. After spending a few months with vimium, I found vim-vixen, which doesn't have these problems.