At the top of the What's New tab there's the first line stating the last time the feed was updated.

I've been seeing for quite some time now an extra line there saying "Not loaded: 1". My guess is that one of the subscribed channels doesn't exists anymore. If that is correct, is there a way to know what channel is other than trying one by one?

If it something else, please, what is it? I won't loose sleep but it is bugging me enough to post about it after not being capable of googling (or duckducking) the answer.