Super easy to use.
Worked great.

It would be nice to see the title, or where in my bookmarks the offending bookmark is located, for future improvement.

Excellent job on finding dead links of varying kinds.

However really poor on finding duplicates. For some reason it's showing folders at the same level as duplicates (:data) which are not other than them being folders. You will delete your tree following through on that. Obviously this must be fixed.

Sir, please also add a way to check if youtube videos have been deleted, thanks.

- this add-on correctly detected quite some dead bookmarks that '404 Bookmarks' add-on had not seen in this location. So very good.
- Dupes it detected were actual *folders*, so deleting them would have brought havoc in my bookmarks library. Not good.

A tool I was looking for a few years... Thanks !

I wonder if "exclusion of folders" could be a little more put forward (I accidentally removed bookmarks of intranet sites).

The generation of screenshots could be a nice feature. It would help removing another kind od of obsolete bookmarks: those whose answer indicates that the site has been moved.

Funktioniert tadellos und ist sehr gut gemacht.

Hello - Just installed this addon - but how do I actually run this thing to clean up my bookmarks ? The screenshots I have seen, but how to get there? Sorry for the silly question.

Very helpful time saving Bookmark organizing add-on, removing duplicate bookmark, merging duplicate folders. Thanks a lot for this. I wish Firefox had these features builtin in Bookmark library.

There was a bit more manual interaction required than i would have liked (e.g. when it absolutely refuses to remove the last copy of a bookmark in batch mode, forcing the user to delete them individually). Also, the URL checker process pops up countless HTTP auth dialogs for sites which use HTTP Basic authentication. i'm not certain that this extension can avoid those, but it is irritating (i've got dozens of them). In any case, it's simple, clean, and easy enough to use, and it allowed me to go through and clean up a great many useless bookmarks.

It actually does what it says, and what's needed. Unlike many other extensions like this, it works to combine trees of folders properly, and then to identify and remove all the duplicate bookmarks in each individual folder.
The addition of an excluded folders is a major bonus when dealing with external bookmark sync tools.