Also there is:

Surfing Keys: https://github.com/brookhong/Surfingkeys

Tridactyl: https://github.com/tridactyl/tridactyl

Both target Firefox, but may have Chrome versions as well.

Some ~10 years ago I used to use a Firefox extension called Vimperator [0]. I then switched to a fork of Vimperator named Pentadactyl [1], because the latter was more complete and stable at the time. And even later I used the Vimium extension on Google Chrome.

But even though I enjoyed these types of extensions, Vim key bindings in the browser powered by these add-ons has always been fragile and prone to stop working all together at times and that eventually caused me to stop using any of them even though I remain a user of Vim and of IDEs with Vim-emulation.

Perhaps these are stable enough today, perhaps not. If I were inclined to go back to having Vim keybindings also in my browser then I would probably want to check out Vieb, as the idea of having it properly integrated into the browser does seem a good idea to me and with Vieb we'd still be getting the Blink engine that Chrome etc is using.

But these days I like to use Brave as my main browser on my MacBook Pro M1, because of the privacy enhancing features that Brave has built into it alongside other nice things. On my iPhone I just use Safari. Occasionally I use Safari on my laptop as well. For example, I have Brave configured to turn all pages into dark mode but some sites become unreadable and then my simple solution because this happens rarely enough to not be distracting is that then I open the page in Safari instead.

Also my usage pattern of browsers has changed. I used to sit on the desktop and read a lot of things. These days I most often read stuff on the phone, and I use the browser on the laptop mainly for looking up things quickly and for using web applications like Google Docs and such. So it's like, one of the main reasons that I used to use Vimperator etc, to navigate by keyboard instead of by mouse, is not as relevant any longer. And even on the laptop, scrolling up and down is smoother and simpler using the touchpad and the spacebar than using Vimperator etc.

When I have the MacBook Pro M1 connected to external keyboard, mouse and monitor I might still benefit a little bit from something like Vimperator. But not enough to be worth the bother anymore, because of the things I mentioned.

[0]: https://en.wikipedia.org/wiki/Vimperator

[1]: https://en.wikipedia.org/wiki/Pentadactyl

Recently discovered this and have been enjoying it a lot. There are some edges but overall works quite well. Also, available for Safari : https://github.com/televator-apps/vimari

I found Vimium C [0] works better for Firefox (some features were broken on Vimium), and it's on Chrome too.

[0]: https://github.com/gdh1995/vimium-c

Also

LinkHints: https://lydell.github.io/LinkHints

Well, for firefox as well. Although on both it lacks the flexibility it used to, due to browser limitations.