[Plasma] X crash when external monitor unplugged with NVIDIA PRIME

I've been using NVIDIA gpu as the default device for X, and plugging and unplugging external monitor in HDMI was no problem on my laptop with -current + KDE5/Plasma. Recently, I moved to PRIME offload, driving X on Intel integrated gpu and running specific applications on NVIDIA with special environment variables.

It does seems to work regarding offloading to dGPU, but I noticed that on unplugging hdmi cable the X server crashes, returning to console with a frozen screen. I have to reboot with SysRq + Alt + B, though no output is actually shown in the console and other commands are unresponsive (changing tty, CTRL + C, etc).

The scenario of unplugging: Laptop lid is closed with the cable on and the external monitor on. I open the lid, both screens are ok, mirroring each other. I remove the cable, laptop monitor keep showing the desktop for a brief moment, then crashes to unusable console with no apparent error lines.

My kernel boot strings:
Code:root=/dev/mapper/[redacted] vga=normal ro resume=UUID=[redacted] resume_offset=[redacted] threadirqs psmouse.synaptics_intertouch=1 acpi_osi='Windows 2015' acpi_osi='Linux' nogpumanager pcie_port_pm=off intel_iommu=on iommu=pt zswap.enabled=1 zswap.zpool=zsmalloc zswap.compressor=zstdI'm also running on modprobe.d:
Code:options nvidia-drm modeset=1Xorg.conf, simplified:
Code:Section "ServerLayout"
Identifier "Layout0"
Screen 0 "intel"
#Inactive "intel"
InputDevice "Keyboard0" "CoreKeyboard"
InputDevice "Mouse0" "CorePointer"
Option "AllowNVIDIAGPUScreens"
EndSection

Section "Module"
Load "type1"
Load "freetype"
Load "glx" #loads dri3
EndSection

....

Section "Monitor"
Identifier "Monitor0"
VendorName "Unknown"
ModelName "[redacted]"
HorizSync 26.0 - 81.0
VertRefresh 24.0 - 75.0
Option "DPI" "96 x 96"
EndSection

Section "Monitor"
Identifier "Monitor1"
VendorName "Unknown"
HorizSync 26.0 - 81.0
VertRefresh 24.0 - 75.0
Option "DPI" "96 x 96"
EndSection

Section "Device"
Identifier "card_nvidia"
Driver "nvidia"
VendorName "NVIDIA Corporation"
BoardName "[redacted]"
BusID "PCI:01:00:0"
Option "HardDPMS" "false"
EndSection

Section "Device"
Identifier "intel"
Driver "modesetting"
Option "AsyncFlipSecondaries" "on"
BusID "PCI:00:02:0"
Option "DRI3" "1"
EndSection

Section "Screen"
Identifier "screen_nvidia"
Device "card_nvidia"
DefaultDepth 24
Option "Stereo" "0"
Option "AllowNVIDIAGPUScreens"
Option "Coolbits" "13"
Option "AllowEmptyInitialConfiguration" "True"
Option "ForceFullCompositionPipeline" "on"
Option "metamodes" "1920x1080_60i +0+0"
EndSection

Section "Screen"
Identifier "intel"
Device "intel"
DefaultDepth 24
Option "Stereo" "0"
EndSectionxorg.log when it crashes:
Code:(--) NVIDIA(GPU-0): [redacted] (DFP-0): connected
(--) NVIDIA(GPU-0): [redacted] (DFP-0): Internal TMDS
(--) NVIDIA(GPU-0): [redacted] (DFP-0): 600.0 MHz maximum pixel clock
(--) NVIDIA(GPU-0):
(II) event7 - .... Wireless Radio Control: device removed
(II) event3 - Power Button: device removed
(II) event14 - Video Bus: device removed
(II) event13 - Video Bus: device removed
(II) event2 - Power Button: device removed
(II) event1 - Sleep Button: device removed
(II) event6 - Logitech ....: device removed
(II) event4 - AT Translated Set 2 keyboard: device removed
(II) event5 - Logitech .....: device removed
(II) UnloadModule: "libinput"
(II) UnloadModule: "synaptics"
(II) UnloadModule: "libinput"
(II) UnloadModule: "libinput"
(II) UnloadModule: "libinput"
(II) UnloadModule: "libinput"
(II) UnloadModule: "libinput"
(II) UnloadModule: "libinput"
(II) UnloadModule: "libinput"
(II) UnloadModule: "libinput"
(II) UnloadModule: "libinput"
(II) NVIDIA(GPU-0): Deleting GPU-0
(WW) xf86CloseConsole: KDSETMODE failed: Input/output error
(WW) xf86CloseConsole: VT_GETMODE failed: Input/output error
(WW) xf86OpenConsole: VT_GETSTATE failed: Input/output error
(II) Server terminated successfully (0). Closing log file.NVIDIA driver (tried with previous versions, same results):
560.35.03

Anyone seen something like this before?