Man I had the link in my comment, I saw the embed too. Maybe it disappeared when I edited my comment iunno. Here https://github.com/calibrain/shelfmark

I had been using one called Stacks but it ate shit recently and the maintainer is awol. Too bad because it was great.

If you’re into Docker containers at all, I just set this one up last night and it does work, eventually. I don’t know if it would fix your problem, but it fixed mine with downloading anything at all.

(Link in below comment, apologies.)