When an image in the list view of FileExplorer is dropped outside the dialog, a duplicate of this image is stuck to the cursor. After selecting another image, the ghost image remains and overlays the upload window.  Follow the attached clip.

Steps to reproduce:
1. Open FileExplorer in Thumbnails mode (or open Editor's Image Manager);
2. Select an image and start dragging it;
3. Drop it outside the dialog;
4. Observe the ghost image on the cursor;
5. Select another image;

Result: The ghost image is not removed and overlays another dialogs.