this is a classic snap, it does not use confinement (or rather very very reduced confinement) … you wont find any denials or audit messages from it …
IIRC codium has a --verbose option that should print all output during startup to the terminal … perhaps that gives you some hints where it fails (i just installed it (on a 22.04 system), it works fine over here)
The --verbose option doesn’t print anything more than the normal run.
/snap/codium/297/usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/gdk-pixbuf-query-loaders: /snap/core18/current/lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.34' not found (required by /lib/x86_64-linux-gnu/libgtk3-nocsd.so.0)
/snap/codium/297/usr/share/codium/bin/../codium: /snap/core18/current/lib/x86_64-linux-gnu/libc.so.6: version `GLIBC_2.34' not found (required by /lib/x86_64-linux-gnu/libgtk3-nocsd.so.0)
I’m using snapd from the edge channel.
snap version
snap 2.58.3+git520.gb0848d7
snapd 2.58.3+git520.gb0848d7
series 16
ubuntu 22.04
kernel 5.15.0-67-generic