This started out as an F.A.Q. entry in the Springheel HOWTO.md, but ended up a bit more complex than I'd expected. The short version is:
- Springheel itself does not and cannot add favicons to generated sites.
- This is unlikely to change for the foreseeable future.
- You do (theoretically) have the ability to hack a favicon in on your own, but I can't offer much in the way of support.