Hello all,
well I installed the Opera GX browser on my work station (Windows 10) and on my notebook (Windows 7).
After the installation on the notebook I replaced the profile directory on notebook with the one from my workstation.
(So everything has the same settings.) -> worked perfectly. 
After that I created a Opera Account and logged myself in with the created account on both devices.
I configured the sync option for bookmarks, history, settings and open tabs. So far everything was good.
I used and tested the browser on my notebook by changing a single setting, placing a new bookmark, opening a new website and surfing through the internet. The browser was closed after that and I wanted to continue on my workstation.
Now I'm having an issue.
I expected that everything I changed in the browser on the notebook should appear in the browser on the workstation, but it didn't. Except for the bookmark, that worked.
I couldn't see the history of my notebbok in the history tap on my workstation.
All open tabs from my notebook were not visible for me on my workstation. (Maybe I couldn't find the correct option, but I expect that the browser (workstation) open the same tabs that I closed the browser (notebook)).
I configured on both devices that they should open with the same tabs that they were closed with.
The browser history was not up to date on my workstation. I couldn't find entries from the session with my notebook.
Now I have several questions.
- Do I have to start the synchoniatione by myself or is there a time period where it happens?
- Is the sync.opera.com site the only option to see my synchonized data? (I configured that every synchonized data should be encoded with personal passphrase. Even when I deconfigure this, the synchonization don't work.)
- maybe an easy one here: The option in top right corner for my account is not visible after logging in. Is somewhere a setting to see this the hole time?
I hope you can help me 
Thank you and have a nice day.
Mike