Thanks. I've tried that, but I don't get an UNSUBSCRIBE option. It's not that I've subscribed to it, and I haven't tapped WATCH at any stage - I've simply commented in the thread at some point and it shows in my PARTICIPATED every time someone else adds a comment. Here is another screenshot of what I see:
OK, I get it now. Sorry. Since you "participated" in that thread it's going to show in "Participated" in the App. That's what "Participated" is. There is no way around that. If you want to see a list of the threads you participated in... well, then there it is.
Sorry to send you on a wild goose chase, but didn't know you were talking about the Mobile App in the beginning.