In case it might be useful to anyone else, I just wrote a quick Chrome extension to download all PDFs on CourtListener when there are multiple attachments to one docket entry.

Screenshot of a CourtListener docket entry with a main document and seven attachments. A green "Download all PDFs" has been added to the bottom, and is highlighted with a pink arrow overlaid on the screenshot.

It also renames the files all nicely so you don't end up with that whole pile of files with names like "gov.uscourts.nysd.590939.407.26.pdf"

Screenshot of Zotero entry with more than 40 files attached. They're named things like "Attach­ment 1 - Exhibit A - Index of Letters in Support of Samuel Bankman-Fried's Sentencin.pdf" and "Main Document - Sentencing Submission.pdf"

I also just added support so it will work on PACER pages (iff you have the RECAP extension installed, and you should!)

Screenshot of PACER docket entry with multiple attachments, with an arrow pointing to a "Download all PDFs from CourtListener" button

If you use PACER and you don't use RECAP, you should rectify that immediately.