An item (I’d guess the first one) stay unread even though everything is “READ” in the feed list. Might it be related to the “second item selected when clicking a feed” bug that was corrected not long ago? I believe it’s the first time that this ever happen to me.
The only way I found to get rid of the icon is the “Mark all as Read”. But if I do that, the yellow items also get read which is not the behavior I’m looking for.