I am trying to delete a bookmark; unlike other bookmarks, its star field is not "blue"; when I click on it, a blue star migrates to the next icon ("show all your bookmarks"), adding another instance of the same bookmark. At this point the star becomes blue and when I click, it shows the "delete" option; when I do so it deletes one copy (the new one) leaving however the original one still in the list. How do I get rid of this "persistent" bookmark ?