Since Sync V2 release has been delayed to Aug 13th from Aug 11 and I have seen no response re this issue I have filed a bug report
Apparently the behavoir I have been seeing for these 2+ weeks is a known issue:
" Same as #11196. Only typed in URL’s are sync’d as of now and not tabs that have links opened via context menu or via external file link"
So Syncing of tabs is only half working.