How about Other bookmarks?

"Unsorted bookmarks" was replaced by "Other bookmarks" a number of new versions in the past.

a "whoops" edit: But the old "Unsorted bookmarks" may still be present, but after that Firefox update the "default folder" became "Other bookmarks". Just left the existing contents of "Unsorted bookmarks" as it was before that update.

Hi Portugal7, how did you confirm that a page was bookmarked? Does Firefox show a blue star in the address bar when you revisit the page, or show it as a starred suggestion when you type part of the address in the address bar?

If you click the blue star, you can use a little trick to discover the current folder location. I have attached a screenshot showing how to open the folder list and see where the bookmark is saved.