Well, up until a few days ago, this site *was* on Grav. I did manage to get basic outgoing webmentions working, but I had no way of having any reply show up on my site, and definitely no way of replying back to it. So thank you very much for your reply, but the only reason I can see it is because I converted the site to WordPress and set up all the IndieWeb plugins. As much as I like the *idea* of hacking away at PHP, IndieWeb is fairly complex if you don’t code for a living.