After some trial and error, this should be a consequence of opening jstor in 'container tabs' (a feature to isolate cookies between different groups of websites). If you're working on the site within a container, then the download fails. If you're using on a non-contained tab, it works.
ie, at least in my case downloading PDFs from jstor works unless I'm using Firefox's 'container tabs' feature (which is usually managed with add-ons like Multi-Account Containers). If you never used or heard of containers then your problem is definitely something different.
Debug ID should be D967154594
ie, at least in my case downloading PDFs from jstor works unless I'm using Firefox's 'container tabs' feature (which is usually managed with add-ons like Multi-Account Containers). If you never used or heard of containers then your problem is definitely something different.