I actually can’t remember as it would have been 6+ months ago now. The issue is probably fixed already by the Debian maintainers / Elementary Team / both.
Likely something with Meson build / apt not playing nicely.
Debian really doesn’t like installing different versions of GUI libraries & their dependencies.
I really like Pantheon Files.
Sounds good in theory, until you want to install scikit-image or other Python libraries which need complex builds.