Good tool for fix URLs or fix parts of the URL, but on complety dynamically generated URL for static website content it fail.
e.g. searching for jobs on https://jobboerse.arbeitsagentur.de.
but this could be solved with saving with unique strings (reference-number) on the website.
Then this duplicates could be found with replacement the dynamic parts of url and a filter ofexpression for name and URL.

now my summary of things good and bad:
(+) very performant
(+) very mighty filtering with regex to find duplicates
(-) it is not very inituitive , a complete debug log in a text file or browser should be usefull
(-) the combobox and the regarding Button are not intuitiv to, a quick improvement could be put the combobox and reagrding butting in a border toshould that it belongs togehter
(-) if no special filter fits or deep subfolders it could be in some case it could confusing , show only bookmark name on the link could help (switchable: Full path bookmark name / short bookmarkname)
(-) i think the the system of local and sync storage is not so good. better where a default profil and create some profiles if the user need and a combo-box to use the filters of the of the selected profile

Feature i really miss is following:
- If I look or filter for duplicates i often would rename a bookmark but then go in the bookmark mangemnet or dive in the subfolder and use the context menu to change to properties is very elaborate.
- export / Impo settings
- creatable and selectable profiles for different filter settings

If thsi feature will implemented i will give 5 points

Crazy unbelievable extension. Saved me hours of cleaning up. I have over 650 dupes and all it took 50seconds and less. All clean good bookmarks. Wow, Martin, Thanx a million for this extension.

Aunque ha ayudado a eliminar carpetas vacías, los marcadores siguen desordenados-duplicados-multiplicados. La mejor solución es la inicial, hace años la actualización de firefox no heredaba de mozilla ningún marcador, simplemente hacías una copia html y la rescatabas. Ahora da igual que no tengas sincronizadas las cuentas, te las hereda y re-duplica again in again. Por favor, vuelvan al método antiguo, es tan sencillo como avisarlo mediante un anuncio-manual en la misma web. Saludos

Worked exactly as described. Saved me from a headache of mistakenly imported dupes! Thank you..!!!

After re-importing my bookmarks, everything was duplicated. This add-on saved me from the headaches. Works flawless. :)

It's a very good add-on to find dupes & empty folders. The other 2 options are kinda useless or I just don't understand their purpose! Why would I want to see non-dupes or all bookmarks? I could do that through FireFox!!

Works great, very clean design. Topp I was looking for such an Extension since years. Thank you so much.

Thing works like a beast. There's several extensions out there that all say they can do this. I'm not sure if it's Firefox's ability to run well or if the developer just knows what's up. This is by far, hands down, your fastest way to delete duped bookmarks. Great work.

Tried different tools..... This tool is best one! Recommended.

Thank you great addon, removed about 3000 duplicates in minutes adn so easy to use..

Just tried to use, while trying to move dupes, got this error: Error after moving 2 bookmarks: Error: result.dateAdded is undefined

(worked normally deleting)

Worst ever. It has made a mess into my bookmarks in Firefox, putting all in a "dupe" file ; when I wrote it off, it drove most of my items into "Other bookmarks" in a complete disorder.

Did the job. Easy to use.

Finally, an add-on that is actually capable of delivering its promise with exceptional speed and efficiency.