I would like to allow authors to submit a hyperlink (linking to supplementary materials on Dropbox or Google Drive, etc) along with their text submissions. The only options I have for “file type grouping” under “Article Components” are Document, Artwork, and Supplementary Content, and all of these options seem to want you to upload a physical document–I would just like a way to upload a hyperlink here. Is that possible somehow? Is there a plugin somewhere…?
It looks like what you need is a custom metadata field. In this previous thread you may find a solution to add it and adapt to your needs:
Public Knowledge Project Team