I think that's an assumed EOL on Pentadactyl because of Electrolysis. The devs don't talk but the community is trying to come up with a way to continue. Vimperator has similar issues with Eloctrolysis, I think?

I hope pentadactyl makes it, cos it's my favorite of the vim extensions. Vimperator just doesn't feel as advanced.

They're both about the same, but vimperator is more frequently updated for compatibility with new Firefox versions.

That alone is much more useful for me.

For me, I'm tracking Firefox esr anyway, so I don't get hit with incompatibility that often.