I want to be able to use the 'upload_dir' in the 'image_upload' field type. I do realise that it does not work. What I am after is the look of the 'image_upload' field in terms of the drag and drop image sorting and multiple file uploads.
So I performed a test with the 'image' field below and it turns out the 'upload_dir' does work for this field too. Even though its not in the docs. So I could use this field but how would I go about adding the image preview and drag and drop support to this?