FOR THOSE WHO ARE NOT CLEAR WHERE IT WORKS. Excellent add-on. Rated 5 out of 5 stars
Here is an explanation of where this add-on works.
I had a struggle to figure out what this add-on refers to in Firefox.
I have customized my Firefox and added a button called "Display bookmarks". When I press it, it opens a sidebar at the left where I can navigate the full list of bookmarks.
It is in this area that this add-on works.
Type a keyword in the Search field. Right-click one of the search results obtained after having entered a keyword.
Then, at the bottom, you have a special area where you can easily see the hierarchy of folders where the particular bookmark result that you have selected is located.
Thanks to the developer for again this excellent add-on.