So, I was unhappy with the CSS for the Zine app, it was a bit buggy. I replaced with something that is a bit worse, but that will become better as soon as the new
masonry CSS grid template goes mainstream on Firefox. Currently, it is behind a flag, so it is only available to advanced users, people who are usually working with Mozilla will know about those flags but normal users don't.
This means that currently it will fallback to a default grid implementation. Eventually, the masonry will just work.