improvement + regression after upgrading from 24.2.7 to 24.3.1

System information

System:
  Host: TavvvaM65 Kernel: 6.12.3-arch1-1 arch: x86_64 bits: 64 compiler: gcc
    v: 14.2.1
  Desktop: Xfce v: 4.18.1 tk: Gtk v: 3.24.43 wm: xfwm4 dm: LightDM
    Distro: Arch Linux
CPU:
  Info: dual core model: Intel Core2 T7200 bits: 64 type: MCP
    arch: Core2 Merom rev: 6 cache: L1: 128 KiB L2: 4 MiB
  Speed (MHz): avg: 1333 min/max: 1000/2000 cores: 1: 1333 2: 1333
    bogomips: 7983
  Flags: ht lm nx pae sse sse2 sse3 ssse3
Graphics:
  Device-1: NVIDIA G72GLM [Quadro FX 350M] vendor: Dell driver: nouveau
    v: kernel arch: Curie pcie: speed: 2.5 GT/s lanes: 16 ports: active: LVDS-1
    empty: DVI-I-1,TV-1,VGA-1 bus-ID: 01:00.0 chip-ID: 10de:01dc temp: 55.0 C
  Display: x11 server: X.Org v: 21.1.14 with: Xwayland v: 24.1.4
    compositor: xfwm4 v: 4.18.0 driver: X: loaded: nouveau
    unloaded: fbdev,modesetting,vesa alternate: nv dri: nouveau gpu: nouveau
    display-ID: :0.0 screens: 1
  Screen-1: 0 s-res: 1920x1200 s-dpi: 96
  Monitor-1: LVDS-1 model: Sharp 0x13bd res: 1920x1200 dpi: 147
    diag: 390mm (15.4")
  API: EGL v: 1.5 platforms: device: 0 egl: 1.4 drv: nouveau device: 1
    drv: swrast gbm: egl: 1.4 drv: nouveau surfaceless: egl: 1.4 drv: nouveau
    x11: egl: 1.4 drv: nouveau inactive: wayland
  API: OpenGL v: 4.5 compat-v: 2.1 vendor: mesa v: 24.2.7-arch1.1 glx-v: 1.4
    direct-render: yes renderer: NV46 device-ID: 10de:01dc

Describe the issue

With 24.2.7 I was getting the following when trying to run opentyrian:

Thread 1 "opentyrian" received signal SIGSEGV, Segmentation fault.
0x00007ffff59b48ba in ?? () from /usr/lib/libgallium-24.2.7-arch1.1.so
(gdb) 

With 24.3.1 it doesn't crash anymore and the game works, but after the next reboot the xfce4 session is completely borked (except the mouse cursor) even when the lightdm with gtk-greeter is displayed correctly.

Regression

Partial ... opentyrian improved, but xfce4 became unusable

Log files as attachment

[ 44.643274] opentyrian[1019]: segfault at 0 ip 00007c26a13b48ba sp 00007ffe08a80f30 error 6 in libgallium-24.2.7-arch1.1.so[fb48ba,7c26a0415000+16cf000] likely on CPU 0 (core 0, socket 0)