Hey @theolivenbaum, apologize for the delay!
I have checked your snap and I see:
read-home-folder:
interface: personal-files
read:
- $HOME
read-installed-apps:
interface: system-files
read:
- /usr/share/applications
To access non-hidden files owned by the user in the user’s home directory, you can plug home which is auto-connected by default on classic systems right away. Are you also willing to access hidden files/directories in the user’s home? If that’s the case that’s where you can plug personal-files but please consider that you need to specify which ones you need since the main purpose of this interface is to import data from existing applications where the snap is the clear owner of the target directory. A final comment in case you are not aware of, snaps have $HOME set to ~/snap/< snapname >/current, this Security policy and sandboxing could help to understand better the env vars and their values.
A similar situation happens with system-files. The interface is specifically used to provide read-only access to system configuration directories created by a non-snap version of an application now running from an equivalent snap. What are you trying to achieve by reading /usr/share/applications?