I had hundreds of bookmarks on my "Bookmark Bar" with folders and subfolders. Now they are gone after upgrading to Opera 28. Fortunately I can see all my bookmarks in the bookmarks.adr file under the old profile directory. But after I copy the bookmarks.adr file from the old profile directory to the new directory, my bookmarks are still missing.

I have also tried importing the bookmarks, but it only imported the bookmarks that were on the Bookmark Bar excluding all the bookmarks that were in the folders.

What can I do to get my bookmarks back? I don't know what my original version of Opera was.