Development on the plugin seems to have stopped two months ago and the repo has been archived. Unfortunately that means that downloading from GH-actions (as advised in the documentation) is impossible, because the download has expired.
Any workarounds (short of using docker)?
You could try forking it and running the action on your own repo.
The free actions limit should probably be enough for what you need.
I found a thread on the jellyfin forums about this: https://forum.jellyfin.org/t-intro-skipper-project-dead
There are already forks of it: https://github.com/ConfusedPolarBear/intro-skipper/forks
Question is, any of those worth switching to?
https://github.com/endrl/jellyfin-plugin-media-analyzer
This fork looks really interesting. I’ve not run it myself but plan on giving it a go soon.
I dunno, I don’t use it myself. If they’re just forked to run the action there should be no difference for you.