I wanted to create a new topic but as I have also a sync problem, I ask here.
I don't have Windows, I can't help for that but you should precise the error. My 3 Android tablets sync very well, except for the Quick access.
Like here: https://forums.opera.com/topic/72436/sync-quick-access but there is no solution.
It normal to have to go in other devices/quick access and modify them manually? Is it not sync like the favorites?