You may need to check the history settings and make sure that you keep history.

• Tools > Options > Privacy > Firefox will: "Use custom settings for history" > "Remember my browsing and download history"

Also make sure that you do not use Clear Recent History to clear the history.

• Tools > Options > Privacy : History: [X] Clear history when Firefox closes > Settings
• https://support.mozilla.org/kb/Clear+Recent+History

Well the thing is Live Bookmarks worked perfectly fine at remembering read post in all previous versions of Firefox, and that was with not keeping history as well as clearing all privacy data via CCleaner. So I'm not sure why we have to compromise our privacy and security when this was never a problem with all previous versions of Firefox.

Found a 3rd party add-on solution to the problem. It's in Beta and a wee bit funky in getting use to, but seems to do the job:

http://projects.protej.com/index.php/liveclick/home/

the speil:

LiveClick is a Firefox addon that aims to give Live Bookmark users what they need. With LiveClick, you can:

• Easily see which Live Bookmarks have new or unread items
• Control how often Live Bookmarks check for new items
• Receive alerts when select Live Bookmarks have new items
• Mark Live Bookmark items as ‘read’
• Hover over a Live Bookmark item to preview its contents
• Click a Live Bookmark’s folder to quickly access its home page
• Use site icons (aka favicons) in place of the default RSS icon

Requiring me to maintain history is not acceptable. Previous versions have not required this, and I'm not going to start doing it now.