It works in Chrome, but most viewers will fix minor corruption in PDFs. qpdf/poppler will tell you if they detect any issues, and they both say it's fine. So I

It works in Chrome, but most viewers will fix minor corruption in PDFs. qpdf/poppler will tell you if they detect any issues, and they both say it's fine. So I suspect the issue is either your viewer, or the file somehow got corrupted on the path from the website to your viewer.