@twolff-wescale If it works in a standalone installation, but not in a regular installation, that implies that there's something messed up with your Opera profile for the regular installation or that something external is interfering with Opera when it's install in its default location.
Thank you. I can't believe I haven't thought of that and it turns out the solution was that easy. It will take me some time to take the bookmarks out of folders they were thrown into, but at least I have them in browser now.
Thanks! This "Options" link is gray and looks like a continuation of the "Terms and Conditions" text. It could be made more visible
But the passwords are still there though... It's possible to bulk remove them, but still: it's not nice that such sensitive information is being imported without even asking...