Hi there, some changes to the Bookmarks Toolbar were rolled out early. Firefox 85 will let you remove Other Bookmarks from the Bookmarks Toolbar with a right-click option. Since that is not available in Firefox 84, you could roll back the new changes this way:

(1) In a new tab, type or paste about:config in the address bar and press Enter/Return. Click the button accepting the risk.

(2) In the search box in the page, type or paste toolb and pause while the list is filtered

(3) Double-click the browser.toolbars.bookmarks.2h2020 preference to switch the value from true to false

After posting my question, I realized others had the same problem. I hope when my browser updates to the next version that I will have the option to show Other Bookmarks or not. But, I followed this recommendation and so far so good. Thanks everyone who contributed their knowledge and experience.

You might be part of a study that has enabled some new bookmark features.

You can check this pref on the about:config page and make sure it is false.

   browser.toolbars.bookmarks.2h2020 = false 

You can open the about:config page via the location/address bar. You can click the button to "Accept the Risk and Continue".

In Firefox 85+ you will be able to right-click this Other Bookmarks button or right-click empty space to hide the Other Bookmarks button on the Bookmarks Toolbar. For now these new features are only enabled if browser.toolbars.bookmarks.2h2020 = true. Once the development of these new features has finished then this pref will be removed. Otherwise you would have to move all bookmarks out of this folder.

Thank you Co-rel and jscher2000 for your help. Problem solved. :-)