When evince says ‘Unable to open document "<BLAH>". PDF document is damaged’

During the past few months I’ve been “Docusign”ing things, and the website lets me download the finished document, which is great. But until now I haven’t been able to view them using CLI tools unless I pointed a browser (firefox in my case) at them.

Finally I applied the LMGTFY principle (the 21st century version of RTFM), I did a web search on the message, which eventually led me to this nice article on superuser.com. The short version of The Answer is:

gs -o FIXED.pdf -sDEVICE=pdfwrite  -dPDFSETTINGS=/prepress CORRUPTED.pdf

That↑ worked great for me, though someone recommends instad -dPDFSETTINGS=/default.