Originally by @snyholm

Currently it is not possible to use a component as the drag start handle ( as in, the component you click to initiate the drag and drop ) and have the drag image to be a parent component. This would be useful when trying to make something like a dashboard widget where you might want to initiate the drag and drop using the header but show the entire parent widget as the drag image.

Imported from https://dev.vaadin.com/ issue #13836