Created attachment 174846 [details]
KDE 6 + Chromium + Proxmox => Scrambled colors

I am experiencing an issue with KDE 6 when running in a Proxmox VM.
If I run Chrome (or any chromium based browser) on with that configuration, the colors are scrambled.

The issue only shows when running as a Proxmox-VM and when using Chrome, and only with KDE 6. Earlier KDE verisons work fine, Firefox as a browser works, and if I run it on a “bare iron” I am also not experiencing the issue.

The issue manifests of color being “inverted” in some way, especiallly skin tones often come out blue. People look like the smurfs. On top of that, what normally appears to be a shadow around the windows, appears as a black box (see screen shot)

I have spent days analyzing under which circumstances this happens.
It seems that the problem is the Combination of KDE 6, Proxmox, and Chromium.

I have posted about this (sorry for not posting links, but I am not allowed to)

On reddit “Chromium Color Glitch/Blue Smurf-Skin/Black Frame”

in the Manjaro Forum “Proxmox + Chromium based brower => Scrambled colors”

in the Proxmox Forum “Proxmox verdreht Farben in Chrome”

Here some configurations I can reproduce the issue with:

Proxmox 8.2.7
Distributions:
Kubuntu 24.10
Manjaro/Plasma (Both Stable and Unstable branch)
To reproduce the issue, once Proxmox is installed, the issue can be reproduced with the distribution’s live CD. Here my configuration/steps to reproduce:

Kubuntu
------------
1. New VM (1 CPU/4 Core/8GB Ram, rest default) - use Kubuntu image above.
2. Boot/in the boot manager use the default (try or install)
3. select “Try Ubuntu”
4. Start-Menu/Konsole; enter:
sudo install chromium
chromium


Manjaro
------------
1. New VM (1 CPU/4 Core/8GB Ram, rest default) - use Manjaro image above.
2. Boot into Manjaro live ISO.
3. Open a terminal
pamac install chromium
< enter > - (don’t install dependencies)
y - (apply the changes)
chromium

I have tested valid Proxmox CPU/graphics card combinations on two completely different physical machines and I can reproduce the problem on both of them - the issue does not occur if I install KDE on the bare iron, but only when using Proxmox.
The issue occurs with all CPUs I have tested, and with all graphics cards except for:
* virtio
* virtio-gl

This issue has also been reported with Proxmox: https://bugzilla.proxmox.com/show_bug.cgi?id=5790