Find duplicates by ISSN, URL, or date fields

I’m repeating a feature request here that I discussed with a rep.

I would like to find duplicates by ISSN, URL, and/or date fields rather than just title or author.

I have thousands of patents in my library and many of them have the same title and authors, but they all have different patent numbers. The patent number field for patent-type references maps to the ISSN field in journal-type references, so checking for duplicates in those fields would be more helpful for bringing up actual duplicates. As things stand, if I check for duplicates within EndNote, it brings up hundreds of spurious matches, to the point that I had to purchase other software to find the duplicate PDFs on my computer and then go through the corresponding entries in EndNote manually to merge/delete them.

Please comment/like if you have similar issues.