I'm having the same issue with both the syncing and the Flow features. I've been trying to connect my Flow feature, but it won't work. I scan the QR code with my phone and receive a code that I can't enter anywhere on my PC. I just keep being brought to a screen to log in again every time I try. I sent an issue email to Opera, but have no idea if they are dealing with this issue. It's strange that the Flow feature works on the mobile version of the browser, but not the PC version of the browser.