Many thanks for the reply.  I did start with the widgets api, but I didn't find any specific description of the 'referenced from' field.  I suppose I should look into the js for the smartfile widget.By the way your link to SmartImage (and the same applies to CQ.form.SmartFile) show this widget marke...

Hi, can you help me understand the expected behaviour of the authoring widget html5smartfile?When I use this widget in an authoring dialogue and drop an image from the content finder onto the drag and drop area, it shows the file name in the editable text field for this component, e.g. 'MyImage.png'...