Great Add-on, but can't download PDFs with recent Waterfox version Rated 4 out of 5 stars

I like PDF Viewer since it allows me to break free of "Adobe Acrobat hell." However, with the latest update to Waterfox 15, I have not been able to download a copy of the PDF at all using the add-on.

This review is for a previous version of the add-on (0.7.1.1-signed).