Drag-and-drop in downloads panel
Currently, it is not possible to drag and drop items from the Downloads Panel. Instead, if you need drag-n-drop functionality, you need to manually open the folder up and drag from there.
Other browsers (i.e. Chrome) let you drag and drop from the downloads bar, why not Vivaldi?
@rocketinventor: Because Vivaldi is still very immature and has some years of coding ahead of it before it is complete. The ability to drag from the download panel has been requested and so the developers are aware of it. But there are some thousands of bugs and feature requests to be gotten to, and a relatively small development team.
For all that, in two years Vivaldi has made more progress than any browser I have ever watched in development over a similar period. So it will get there.