If you have hundreds of bookmarks in different folders like I do you might know the problem that bookmarks are added from time to time that already exist in your list. It is not that easy to manage the bookmarks and keep an overview over them all. A complicated folder structure with many subfolders is adding to the problem. It really does not help to check your bookmarks manually every know and then, this takes to long and does not prevent that duplicate bookmarks are added at a later date again. The Firefox extension Bookmark Duplicate Detector is helpful for users with a lot of bookmarks.

