I have four folders (plus a number of single bookmarks) on my Bookmarks bar. Each folder contains a few bookmarks.
After activating sync, this has started to happen:
Each folder now contains the original bookmarks, plus the bookmarks from another folder on the bar.
The other folder still contains its original bookmarks, plus the bookmarks from a third folder. And so on.

No bookmarks have gone missing, but there are a lot of duplicates. I have deleted the duplicates several times, but they keep coming back.

Opera 29, Windows 7.

Would be really nice if you could bring back the old Opera functionality of panning large images by pressing the spacebar.
Using the scroolbars is really awkward in comparison.

I was referring to left click. So how about Ctrl-Shift-left click?

Don't know if this is of any help, but it works like this for bookmarks: (Opera 23)

Click: Opens in the same tab

Shift-click: Opens in a new window

Ctrl-Shift-click: Opens in a new tab

Ctrl-click: Opens in a new tab, but in the background