This was probably the problem.  Chrome defaulted to synchonizing bookmarks while Firefox did not.  I have configured all my chrome browsers to NOT sync bookmarks and now the duplicated bookmark issue is not occuring.  

Thank you!

Yes the problem was fixed soon after I received your comment.  Thank you.  And I apologizer for not replying sooner.

Yes, the site is back up now.  Working well.  Thank you.