KDE Plasma Kwin crashes after signon [Solved]

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[Solved] downgrading back to Linux kernel 6.6.57 stopped Kwin from crashing. I don’t know why I can’t run 6.10 or 6.11 like I can in Arch Linux, but this will work for now.

KDE Plasma 6.1.4 was the last version to work for me in NixOS. From Plasma 6.1.5 till the most recent 6.2.1.1, after logging in via sddm, it takes about 1 minute for the desktop to appear, and 30 seconds later, Kwin crashes and I’m back at the sddm display manager.

I have two drives in my computer, Arch Linux and NixOS unstable channel. Plasma works in Arch with the same exact Linux kernel, Nvidia driver, and Plasma version. I can only conclude that there must be something wrong with how it’s built in NixOS, or a problem with my configuration. Any help would be appreciated!

Linux 6.11.4
Nvidia Driver 560.35.03
KDE Plasma 6.2.1.1

configuration.nix:

  # Use latest kernel
  boot.kernelPackages = pkgs.linuxPackages_latest;

  # fix for nVidia wayland plasma 6
  boot.kernelParams = [
    "nvidia-drm.fbdev=1"
    "nvidia-drm.modeset=1"
    ];

 services = {
    desktopManager.plasma6 = {
      enable = true;
      enableQt5Integration = true; #disable for qt6 full version
    };
    displayManager = {
      defaultSession = "plasma";
      sddm = {
        enable = true;
        wayland.enable = true;
      };
    };
};
############## NVIDIA ##############

  # Enable OpenGL
  hardware.graphics = {
    enable = true;
  };

  # Load nvidia driver for Xorg and Wayland
  services.xserver.videoDrivers = ["nvidia"];

  hardware.nvidia = {

    # Modesetting is required.
    modesetting.enable = true;

    # Nvidia power management. Experimental, and can cause sleep/suspend to fail.
    powerManagement.enable = false;
    # Fine-grained power management. Turns off GPU when not in use.
    # Experimental and only works on modern Nvidia GPUs (Turing or newer).
    powerManagement.finegrained = false;

    # Use the NVidia open source kernel module (not to be confused with the
    # independent third-party "nouveau" open source driver).
    # Support is limited to the Turing and later architectures. Full list of 
    # supported GPUs is at: 
    # https://github.com/NVIDIA/open-gpu-kernel-modules#compatible-gpus 
    # Only available from driver 515.43.04+
    # Currently alpha-quality/buggy, so false is currently the recommended setting.
    open = true;

    # Enable the Nvidia settings menu,
	# accessible via `nvidia-settings`.
    nvidiaSettings = true;

    # Optionally, you may need to select the appropriate driver version for your specific GPU.
    package = config.boot.kernelPackages.nvidiaPackages.beta;
   };

  ############## /NVIDIA ##############