Opera 32 developer channel has got another update, build 32.0.1910.0 has been released for Windows, Mac and Linux platforms and is available to download. This release brings a tree view or nested folders for bookmarks, Opera developer now has a hidden feature for heart menu feature (could be temporary) which lets you customize the thumbnail added to the bookmark via Heart menu. This version includes Sync service improvements.
Tree view for bookmarks
This version shows the full tree in the bookmark manager and bookmark pop-up. “Our bookmark manager now delivers the well-known concept of nested folders in the sidebar. You can drag and drop folders, and expand and collapse them to view their contents. Organize your bookmarks nice and easy, as you like it to be.”
Heart menu customization
When you add a new bookmark, hover over the thumbnail in the Heart menu, use Scroll wheel to zoom into the page content and move the image around and set desired part of the page as thumbnail.