[lcbiazon]

It's a shame. What I did is installing VimFX, that is e10s ready, and stick around using for some weeks, trying to reproduce the same workflow I have for years with vimperator.

It's a pain at first, but I got used to it and now I don't have to care if vimperator/pentadactyl will be ported or not.

[wz1000]

IIRC, even the architecture VimFX is built on is planned to be obsolete by the end of the year.

[hvis]

Its main developer, however, is looking into implementing the necessary WebExtensions API: https://bugzilla.mozilla.org/show_bug.cgi?id=1215061