Haha, okay, I just made up that name right now. But there's something like that in NoorNote.
As you might have seen in the follow list, for every follow, NoorNote shows the mutual status below it in green. The link "Check for changes" refers exactly to that, to the mutual state.
The first time, it can't check anything because it needs an initial snapshot to compare against in the future. So go to follows list and click on the link. It takes a while (depending on how many people you follow) until eventually you get the message "Initial Snapshot saved. Changes will be detected on next check."
If you do this check again a few days later, now it has a snapshot to compare against.
And if there are changes in the mutual status, they'll be displayed. All the new mutuals and those that used to be but aren't anymore. If you just press "Close," the same changes, plus any new ones, will show up again. If you press "Mark as seen," they won't be considered in the next check.
Anyway, you can safely close that modal because these changes also end up in your notifications.
There, you can check each user again to see if it's really true. Sometimes there are small errors, so it's worth it to also open the user's profile beforehand. The info in the profile is more reliable.
Well, once you have this loyalty info and you've confirmed it, do whatever you want with it.