[dexterleng]

It actually technically could support Firefox/chrome, but I have disabled it because enabling accessibility on chrome breaks window managers.

Also vimium will always be faster than vimac due to how slow the accessibility API is.

I would recommend using both for now.

[mkskm]

One missing piece worth noting is Vimium doesn't seem to support navigating preferences, bookmarks, etc. in Firefox or anything in the toolbar. Not sure if that is possible solely with the WebExtensions API.