Code review comment for ~paelzer/ubuntu/+source/libpam-mount:lp-1804408-LUKS2-support-cosmic

+1, just some suggestions inside.

I was also going to suggest that the script be made idempotent, that helps a lot when iterating over it with enhancements or changes without having to clean up manually before each new run, but that makes it a bit more complicated than needed at this time (check user before adding, or remove user at the end, add traps, etc).