Some little things can be improved.

Add an option to Drag&Drop bookmarks on folder icons (without opening each of them) and will be perfect!
At the moment if I drag a bookmark on a folder icon it will be moved below and not inside (yes, I read the FAQ #5 but I'd like a Windows-style-behaviour, it would speed up my work)

tres pratique

Gives me creeps. Searching for duplicates, then removing them makes me believe I removed both duplicates and original ones and lost data, because even original disappears from duplicates search results. Then later I realize: "oh, it's OK". Also would like automatic bulk duplicates removal instead of having to individually manually remove them.

This is really useful. I hope it will continue to be developed. Two suggestions: sort by clicking column headers, and remember column widths. I find the Name column too narrow (I want to read the whole name but don't need to see the whole URL), but if I drag the divider it doesn't change permanently.

Really the best way to edit many bookmarks in many folders as I often do (move, delete, create new structures ...). This works best in the NC / two panel view.
The programmer has created a powerful tool for users who want to create their own structures for many different topics with many links - here is the moving over two panels unbeatable. An extensive but chaotic collection of links after a surfing session can be arranged in the best possible way.

Wonderful for the future would be the possibility to change icons and font sizes - that would be good for the user. Multi- Select with the shift-key was not possible, but to collect single links with the control-key to mark them worked.

Conclusion for me: long and eagerly awaited tool, everything offline, no data-grabbing cloud, no restricting automatics. A little more fine-tuning and ready is a really cool tool.