Very nice, useful and attractive Noté 5 sur 5 étoiles
But I have few suggestions.
1. In addition to 7 predefined bakgrounds to give an ability to add some image as wallpaper bakground.
2. The tumbail support is great, but when I open a folder with, let say, 30 bookmarks, it is difficult to provide 30 thumbails. That is why usually most of bookmarks are represented as Earth Sphere and I understand why. My proposal is to represent the text of Description field in this case (or part of it if the text is big).
I can explain why it is useful, although less nice.
The average user has 2-3 thousands bookmarks, and for 90% from them he just doesn't remember what this bookmark represent and even why this url was bookmarked.
But having the ability to get brief description of every bookmark, the user can easily recovery his memory and clean up his bookmark kingdom.