Hi BobJug, I haven't seen the beta release yet. Where do the unwanted items appear? More specifically:

• Bookmarks Toolbar
• classic Bookmarks Menu on the menu bar
• Bookmarks Menu displayed by the bookmarks button on the main toolbar

Of those, the Bookmarks Toolbar is usually easy to edit (delete or move the item to a subfolder) and the others it depends on what section it appears in.

Bookmarks Menu displayed by the bookmarks button on the main toolbar. I assumed it was a setting that somehow got changed while I was trying to do something else.

There is a way to trigger Firefox to re-add certain default "smart" folders. For example: Restore the default Smart Bookmarks Folders. But that would be hard to do by accident; possibly if you removed your prefs.js file that could trigger it.

Anyway, unless it has been made a "fixed" folder that can't be moved, you probably can move or delete it.

As a footnote:

This thread relates to the Bookmarks button on the main toolbar (next to the star).

Another thread suggests it might not be move Recently Bookmarked from its new position on the Bookmarks menu that drops from the menu bar on a Mac. https://support.mozilla.org/questions/1133866

I had the same problem in v49.0. Here's what I did:

clicked on Bookmarks right-clicked Recently Bookmarked selected Hide Recently Bookmarked

The Recently Bookmarked folder shows but the bookmarks contained therein no longer take up space in the bookmark list.