Black screen with white underscore cursor on startup

[Astralchroma]

Hi, I'm having an issue with COSMIC on NixOS (nixpkgs). The greeter crashes instantly when it starts, leaving the screen black with a white underscore cursor on startup, here's the relevant log output from journald. It references some sort of missing file, but I don't know what file it's referring to or why NixOS won't have created it automatically.

Sep 29 13:34:07 lithium systemd[1]: Started Session 1 of User cosmic-greeter.
Sep 29 13:34:07 lithium greetd[2254]: gkr-pam: gnome-keyring-daemon started properly
Sep 29 13:34:07 lithium .cosmic-comp-wrapped[2283]: shortcuts custom config error: GetKey("custom", Os { code: 2, kind: NotFound, message: "No such file or directory" })
Sep 29 13:34:07 lithium .cosmic-comp-wrapped[2283]: thread 'main' panicked at 'Failed to load window rules config: Io(Os { code: 13, kind: PermissionDenied, message: "Permission denied" })': src/config/mod.rs:263
                                                       0: log_panics::Config::install_panic_hook::{{closure}}
                                                       1: std::panicking::rust_panic_with_hook
                                                       2: std::panicking::begin_panic_handler::{{closure}}
                                                       3: std::sys::backtrace::__rust_end_short_backtrace
                                                       4: __rustc::rust_begin_unwind
                                                       5: core::panicking::panic_fmt
                                                       6: core::result::unwrap_failed
                                                       7: cosmic_comp::config::Config::load
                                                       8: cosmic_comp::state::State::new
                                                       9: cosmic_comp::main
                                                      10: std::sys::backtrace::__rust_begin_short_backtrace
                                                      11: main
                                                      12: __libc_start_call_main
                                                      13: __libc_start_main_alias_1
                                                      14: _start
Sep 29 13:34:07 lithium greetd[2254]: pam_unix(greetd:session): session closed for user cosmic-greeter
Sep 29 13:34:07 lithium greetd[1710]: error: check_children: greeter exited without creating a session
Sep 29 13:34:07 lithium systemd[1]: greetd.service: Deactivated successfully.
Sep 29 13:34:07 lithium systemd[1]: greetd.service: Consumed 19ms CPU time, 8.1M memory peak, 3.8M read from disk.
Sep 29 13:34:07 lithium systemd-logind[1471]: Session 1 logged out. Waiting for processes to exit.

[bafoah]

Same issue, I forgot the exact error, but it say missing display monitor (despite monitor being plug in - DP), I use NVIDIA, and reinstalling driver seem to fix it, purge all NVIDIA related, then reinstalling system76-driver-nvidia. Oh, and also when in tty screen after a few second it keep quiting tty screen and coming back to black screen with underscore blinking cursor

Occasionally (after monitor off) in graphical interface always loses focus (like there is something that keep pressed esc key), temporary fix is to enter tty, then restart cosmic-greeter service.

There is one-time problem, when login-screen, when you input password, it freeze, cannot enter tty. For this one simply reinstalled cosmic-greeter seem to fix this problem.

[thesecretlifeofabunny]

Also on NixOS - Unstable channel, had this exact same issue.

Commented out the "services.displayManager.cosmic-greeter.enable = true;" in my configuration and then my computer was able to boot just fine.

Haven't had issues until the recent update, maybe from this commit https://github.com/NixOS/nixpkgs/commit/5dca5c28b4cd6ad678b4ed7f81a69d9011393e1a?