[wsha]

Sadly it's not realistic. Even if someone were to put in the time to make it work, Vimperator would just break again within the next year when XUL addons are deprecated in favor of WebExtensions, and unfortunately WebExtensions do not support all the features of Vimperator. You can use VimFx for now, but again it is a XUL addon and would take a massive amount of work to port to a WebExtension. Hopefully someone can get Vimium or cVim ported over as a WebExtension. I have played around some with this but haven't got it to work. It seems some of the needed API's are missing from WebExtensions at the moment.

[pmoriarty]

Pentadactyl is also going to break then, for the same reason. That's why I've been moving from Firefox to Pale Moon, where Pentadactyl continues to work. I expect Vimperator will continue to work on Pale Moon too.