I found the Menu Bar and Bk Mks toolbar and made sure both were ticked, then clicked done - but bk mks are still not there when I open FF I can't find 'Restore the menu bar in FF"

I don't know what I did but the bookmarks are back. Thanks for your advice - and your patience! Your commitment was much appreciated.

I'm glad to hear it's back to normal, and I think the only explanation is your persistence.