Just downloaded v2.90 and first thing I did is delete
all the standard news feeds that come with it. Then I
added my own news feed and hit the sync button to get
the news feeds. What happended then (you can see in the
status bar) is that the app still checks the deleted
feeds for updates.
So I guess when deleting feeds from the Interface you
did not remove them from your internal checklist. When
restarting the app the problem is obviously gone.
So just a minor issue.