Thanks for the implementing the autofill from the jstor stable, it has been now possible automatically populate references from the url. IN the long run, I think this feature has to grow to other types of url links too. Bookends can try to find references from the url addresses: using the urls just like the doi sources.
But, my present request still revolves around jstor. Since BE is already able to find the references from the url, I am now requesting if extracting the url from the first page of the pdf would be possible.
All jstor articles come with a cover page. The cover page always contains: http://www.jstor.org/stable/xyzabc where the xyzabcd is the actual address of the individual article.

I was wondering if it is possible to get the url from the cover page; just like Get DOI feature.
(by the way; I tried Mendeley and Zotero for this: since they claimed to have metadata extraction. Mendeley fill them all. Only about 15% of the articles are correctly filled, however. The rest of the entries are either incomplete or filled with wrong data. Zotero failed after extracting the data from about 15 articles. The extraction relied on google scholar; and, it blocked it immediately).