Critical kwin_wayland errors

[medin]

Booting to desktop is successful, but kwin_wayland started showing some critical errors in KSystemLog:

Operating System: Manjaro Linux  
KDE Plasma Version: 6.5.1 
KDE Frameworks Version: 6.19.0 
Qt Version: 6.10.0 
Kernel Version: 6.17.7-1-MANJARO (64-bit) 
Graphics Platform: Wayland

11/7/25 12:47 PM	kwin_wayland	Failed to compile fragment shader: 
 "0:19(18): error: could not implicitly convert operands to arithmetic operator\n0:19(17): error: operands to arithmetic operators must be numeric\n\x00"
11/7/25 12:47 PM	kwin_wayland	line 0:"uniform sampler2D texUnit;"
11/7/25 12:47 PM	kwin_wayland	line 1:"uniform mat4 colorMatrix;"
11/7/25 12:47 PM	kwin_wayland	line 2:"uniform float offset;"
11/7/25 12:47 PM	kwin_wayland	line 3:"uniform vec2 halfpixel;"
11/7/25 12:47 PM	kwin_wayland	line 4:""
11/7/25 12:47 PM	kwin_wayland	line 5:"varying vec2 uv;"
11/7/25 12:47 PM	kwin_wayland	line 6:""
11/7/25 12:47 PM	kwin_wayland	line 7:"void main(void)"
11/7/25 12:47 PM	kwin_wayland	line 8:"{"
11/7/25 12:47 PM	kwin_wayland	line 9:"    vec4 sum = texture2D(texUnit, uv + vec2(-halfpixel.x * 2.0, 0.0) * offset);"
11/7/25 12:47 PM	kwin_wayland	line 10:"    sum += texture2D(texUnit, uv + vec2(-halfpixel.x, halfpixel.y) * offset) * 2.0;"
11/7/25 12:47 PM	kwin_wayland	line 11:"    sum += texture2D(texUnit, uv + vec2(0.0, halfpixel.y * 2.0) * offset);"
11/7/25 12:47 PM	kwin_wayland	line 12:"    sum += texture2D(texUnit, uv + vec2(halfpixel.x, halfpixel.y) * offset) * 2.0;"
11/7/25 12:47 PM	kwin_wayland	line 13:"    sum += texture2D(texUnit, uv + vec2(halfpixel.x * 2.0, 0.0) * offset);"
11/7/25 12:47 PM	kwin_wayland	line 14:"    sum += texture2D(texUnit, uv + vec2(halfpixel.x, -halfpixel.y) * offset) * 2.0;"
11/7/25 12:47 PM	kwin_wayland	line 15:"    sum += texture2D(texUnit, uv + vec2(0.0, -halfpixel.y * 2.0) * offset);"
11/7/25 12:47 PM	kwin_wayland	line 16:"    sum += texture2D(texUnit, uv + vec2(-halfpixel.x, -halfpixel.y) * offset) * 2.0;"
11/7/25 12:47 PM	kwin_wayland	line 17:""
11/7/25 12:47 PM	kwin_wayland	line 18:"    gl_FragColor = (sum / 12) * colorMatrix;"
11/7/25 12:47 PM	kwin_wayland	line 19:"}"
11/7/25 12:47 PM	kwin_wayland	line 20:""
11/7/25 12:47 PM	kwin_wayland	line 21:""

[ben2talk]

The shader code in KWin’s Wayland compositor contains:

• Division of a vec4 by an int (sum / 12) → must be sum / 12.0.
• Wrong multiplication order (vec4 * mat4) → must be mat4 * vec4.

The shader code in KWin’s Wayland compositor contains invalid GLSL operations, which trigger compilation errors on strict drivers.

Operating System: Manjaro Linux
KDE Plasma Version: 6.5.2
KDE Frameworks Version: 6.19.0
Qt Version: 6.10.0
Kernel Version: 6.17.7-1-MANJARO (64-bit)
Graphics Platform: Wayland
Processors: 12 × AMD Ryzen 5 5600G with Radeon Graphics
Memory: 17 GB of RAM (16.1 GB usable)
Graphics Processor: AMD Radeon Graphics

Pasting from konsole kinfo gives slightly fuller detail - is this nVidia (just a stab in the dark here)?

Otherwise it’s possibly some other kwin effect or hmmm IDK really… looks like an upstream issue.

[medin]

This happens with two laptops running on intel iGPUs without any extra GPU.

This also happens with Plasma Wayland 6.5.2.

Edit:

The same errors appear in Plasma Wayland 6.5.2 with kernel 6.6.116, and the situation is much worse: the whole panel become too white and unusable