As of today I can't run Medium. Every boot gives me an error message: "Unable to initialize the Oculus Rift" The log file says "couldn't initialize libovr" and "couldn't initialize rift". I haven't loaded it in a while, but in case I missed an update, I tried deleting and reinstalling it. Still no luck. No other application is suffering in this manner which reassures me that it's not a hardware issue.
It took a clean install of Oculus Home to do it, but I got it running in the end. For a while now, Oculus home had been saying "I'm gonna download an update for Home, honest, I am. I'm doing it right now. You just wait. It's gonna be great." and I'd been ignoring the fact that it never seemed to actually do that. I guess the runtime had gotten out of step with features Medium expected to be able to use and that's why I couldn't load it. In any event, it's back up and running now, thank goodness.