I noticed that getting the threads in which users are participating, ie the Participating tab on Github, is as easy as flipping this value to true... feels like a low-cost feature, maybe under the "View All" tab in the more options alert controller?
I don't know if there is a way to get a count of those Participating threads beforehand. That would be really nice.
I also noticed the v3 api provides a reason for each notification and we're capturing capturing it here. Probably a stretch but an even softer touch could be to use that information to make an inference about whether a user is participating in a thread and convey it in the UI somehow.

What's the value here?
My thought was providing the Participating Tab functionality:

I always shoot straight for that tab, but I could be missing something.
Interesting! I don't think I've _ever_ used that tab before.
At the very least, we could add this into the ... menu bar item? Under "View All" .
Okay no probs, I'll close this issue. If there's ever a stampede of users demanding this feature, its a ~ 5 min job to build.