Steam causes desktop to log out, help?

I’m having a problem like this post where launching Steam causes NixOS to close out of my session and go back to the start menu:

I’ve tried using “steam --reset”, but the issue still persists, and it just started doing it today.

nix-info output:

 - system: `"x86_64-linux"`
 - host os: `Linux 6.12.53, NixOS, 25.05 (Warbler), 25.05.811497.33c6dca0c0cb`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.28.5`
 - channels(root): `"nixos-25.05"`
 - nixpkgs: `/nix/store/fi8hp0d5i62ny4n7pbw3nbx3c8zdzd8w-nixos-25.05/nixos`

My DE is Cinnamon on X11, and I’m also using the proprietary nvidia package as well.

Can you share the contents of:

journalctl --user --boot

… after one of these crashes? Ideally by logging into a tty instead of your DM (by pressing ctel+alt+F3) so that you keep the noise to a minimum.

Also share your configuration.nix while you’re at it.