It kind of works - it does perform the basic function of storing a note or description for your bookmarks. But there are a lot of issues:

* It was tricky to import notes in the first place. It seemed not to be doing anything. A progress bar or other sort of indicator would help.
* Seems to only work at certain window sizes. Its sidebar wouldn't open when I had the window snapped to half-width (at 1920x1080).
* Does not recognize new bookmarks as soon as they are made. You must close and reopen the sidebar to be able to add a note.
* Can't add notes at folder level.
* Filter/search should display results in a list manner similar to history, rather than having to click through and dig to find individual hits.
* No way to delete notes. You can blank out the text, but the blue icon indicating the presence of a note remains.
* Takes several seconds of apparently doing nothing to load the bookmarks when opening the sidebar.
* Sometimes will only load notes on first open, or close and reopen - sometimes if you change to History or Bookmarks in its menu and then back to Notes, nothing loads.
* In Other Bookmarks, I got a lot of empty descriptions erroneously imported (they really were empty, not a single space character or anything like that) that can't be deleted.

I exported my bookmarks to HTML, but now I can't find any way to import them to this extension. I'm rating this poorly for lack of clear functions. I use the descriptions to save location data and contact information for companies, people, etc., very useful and would be inconvenient to store away from the web URL.

Good try, but doesn't work. Syncs a few bookmark notes on a virgin install, but after I import my original file with a hundred notes, sync doesn't work. Developer seems to have lost interest.

I've had to disable the extension 'cos is freezing firefox :/, I'll try with future versions to check if it is fixed.

1st off, everything is still gone. I would have to start all over but I need the old remarks to remember what's in them. I'm old. I forget stuff. 2nd this is like having to do double duty more than just clicking on properties. It's a good try but probably won't use it.

Nice and useful for new users.
But how to restore my way too many bookmark notes I collected over more than 10 years?
Sorry but Firefox is going to be replaced soon in my computers. Too many features are being removed suddenly without any prior information.

Update: I found a Page Memo extension that seems to work for now. It can store notes per URL and displays it on the page. Includes an import/export feature as well.
Original Review
This add-on needs the ability to import and export notes. I use some of them for home and some for work so having them backed up to a file is a necessity. It would also be nice if it could indicate which bookmarks had a note. Also, the layout should be the same as the bookmarks sidebar.