I love that these extensions exist and in theory they sound awesome. Unfortunately for a few reasons I've never been able to get in the habit of using Tridactyl (or any vim browser addon):
it doesn't play nice with Google drive apps (which my company uses extensively), so if I use the vim shortcuts to cycle between tabs and open a Google doc, the next time I try to cycle tabs it will instead start typing in the document. (Alternatively I would never be able to interact with Google docs without manually enabling ignore mode)
hint mode works really well for some sites but a lot of sites have multiple anchors close together (eg one for an icon, one for text and one behind both) which leads to longer hints and difficulty figuring out which hint to actually use
Firefox doesn't allow you to rebund the default "/" search (quick find) cycle keys. The default is c-G for next (not sure about previous); I would like to use n/N
On simple and well-designed "dumb" webpages it works amazing. I wish more sites were designed that way, but unfortunately a lot are made with the assumption of a mouse/touchscreen :(
I agree, there are a bunch of annoying limitations. But it's better than nothing. To me the best vim based browser is qutebrowser, too bad it's using chromium.
These are the reasons I'm stuck on qutebrowser. It's a great browser and project, but I'd love to move away from chromium. If Firefox allowed customizing all these global key bindings I would make the switch.