In Vega Discover, the act of bookmarking an item that is already added to a list in your profiles only deletes the item from your list. A patron from one of our libraries wanted to add functionality where instead of the item being deleted, it would open up the bookmarks tab and allow you to either delete the item from the previously added list or add it to a new/pre-existing list. This provides better management of patron lists and does not require the user to have to re-save/un-save their item from an existing list.