Bug 493618

Perhaps related to the fact that my logs are full of "qt.qpa.wayland: Creating a fake screen in order for Qt not to crash"?

Could be indeed. Can you attach the output of `kscreen-doctor -o`?

Here it is:

Output: 1 eDP-1
        enabled
        connected
        priority 1
        Panel
        Modes:  0:2880x1800@120*!  1:2880x1800@60  2:1600x1200@60  3:1280x1024@60  4:1024x768@60  5:2560x1600@60  6:1920x1200@60  7:1280x800@60  8:2880x1620@60  9:2560x1440@60  10:1920x1080@60  11:1600x900@60  12:1368x768@60  13:1280x720@60 
        Geometry: 0,0 1646x1029
        Scale: 1.75
        Rotation: 1
        Overscan: 0
        Vrr: incapable
        RgbRange: Automatic
        HDR: disabled
        Wide Color Gamut: incapable
        ICC profile: none
        Color profile source: sRGB
        Brightness control: supported, set to 30%
Output: 2 Unknown-1
        disabled
        connected
        priority 0
        Unknown
        Modes:  0:2880x1800@60*! 
        Geometry: 1646,0 1440x900
        Scale: 2
        Rotation: 1
        Overscan: 0
        Vrr: incapable
        RgbRange: unknown
        HDR: incapable
        Wide Color Gamut: incapable
        ICC profile: none
        Color profile source: sRGB
        Brightness control: supported, set to 100%

I can even enable that unknown screen, but nothing is attached to the laptop at all.

Same issue

>  ❯ inxi -Gxx
>  Graphics:
>  Device-1: Intel Meteor Lake-P [Intel Arc Graphics] vendor: Lenovo
>  driver: i915 v: kernel arch: Gen-13 ports: active: eDP-1 empty: DP-1, DP-2,
>  DP-3, DP-4, DP-5, HDMI-A-1 bus-ID: 00:02.0 chip-ID: 8086:7d55
>  Device-2: Bison Integrated Camera driver: uvcvideo type: USB rev: 2.0
>  speed: 480 Mb/s lanes: 1 bus-ID: 3-9:3 chip-ID: 5986:1199
>  Display: wayland server: Xwayland v: 24.1.2 compositor: kwin_wayland
>  driver: N/A display-ID: 0
>  Monitor-1: eDP-1 res: 1920x1200 size: N/A
>  API: EGL v: 1.5 platforms: device: 0 drv: iris device: 1 drv: swrast gbm:
>  drv: iris surfaceless: drv: iris wayland: drv: iris x11: drv: iris
>  API: OpenGL v: 4.6 compat-v: 4.5 vendor: intel mesa v: 24.1.7 glx-v: 1.4
>  direct-render: yes renderer: Mesa Intel Arc Graphics (MTL)
>  device-ID: 8086:7d55 display-ID: :0.0
>  API: Vulkan v: 1.3.290 surfaces: xcb,xlib,wayland device: 0
>  type: integrated-gpu driver: N/A device-ID: 8086:7d55 device: 1 type: cpu
>  driver: N/A device-ID: 10005:0000
>  ❯ kscreen-doctor -o
>  Output: 1 eDP-1
>  enabled
>  connected
>  priority 1
>  Panel
>  Modes:  0:3840x2400@60*!  1:1600x1200@60  2:1280x1024@60  3:1024x768@60  4:2560x1600@60  5:1920x1200@60  6:1280x800@60  7:3840x2160@60  8:3200x1800@60  9:2880x1620@60  10:2560x1440@60  11:1920x1080@60  12:1600x900@60  13:1368x768@60  14:1280x720@60
>  Geometry: 0,0 1920x1200
>  Scale: 2
>  Rotation: 1
>  Overscan: 0
>  Vrr: incapable
>  RgbRange: Automatic
>  HDR: disabled
>  Wide Color Gamut: incapable
>  ICC profile: none
>  Color profile source: sRGB
>  Output: 2 Unknown-1
>  disabled
>  connected
>  priority 0
>  Unknown
>  Modes:  0:640x480@60*!
>  Geometry: 1920,0 640x480
>  Scale: 1
>  Rotation: 1
>  Overscan: 0
>  Vrr: incapable
>  RgbRange: unknown
>  HDR: incapable
>  Wide Color Gamut: incapable
>  ICC profile: none
>  Color profile source: sRGB
>  ~ ❯

Operating System: Fedora Linux 40
KDE Plasma Version: 6.1.5
KDE Frameworks Version: 6.6.0
Qt Version: 6.7.2
Kernel Version: 6.10.11-200.fc40.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 22 × Intel® Core™ Ultra 7 165H
Memory: 62.2 GiB of RAM
Graphics Processor: Mesa Intel® Arc
Manufacturer: LENOVO
Product Name: 21KVS02K00
System Version: ThinkPad P1 Gen 7

This seems to be a kernel bug:
https://gitlab.freedesktop.org/drm/i915/kernel/-/issues/12160

And a possible fix:
https://gitlab.freedesktop.org/drm/misc/kernel/-/commit/ad604f0a4c040dcb8faf44dc72db25e457c28076

I confirm this is fixed in linux 6.11.1.

*** This bug has been marked as a duplicate of bug 493810 ***