Bug 510759

Summary: Chromium brightness is inversly related to HDR brightness on wayland
Product: [Plasma] kwin Reporter: Jakub <jjaruszewski>
Component: colour-managementAssignee: KWin default assignee <kwin-bugs-null>
Status: RESOLVED UPSTREAM    
Severity: normal CC: xaver.hugl
Priority: NOR    
Version First Reported In: 6.4.5   
Target Milestone: ---   
Platform: Other   
OS: Linux   
Latest Commit: Version Fixed/Implemented In:
Sentry Crash Report:
Attachments: Comparison

Description Jakub 2025-10-18 17:37:10 UTC 
Created attachment 185884 [details]
Comparison

SUMMARY

If chromium uses WP_COLOR_MANAGER_V1_RENDER_INTENT_PERCEPTUAL it's wayy to dark and its brightness is inversly related to HDR brightness on wayland

Specifically this is a side effect of: https://chromium.googlesource.com/chromium/src/+/78295f48c220860f587ce266227e0011d9a3ec41
which fixes https://issues.chromium.org/issues/449170664

The change was to replace WP_COLOR_MANAGER_V1_RENDER_INTENT_RELATIVE with WP_COLOR_MANAGER_V1_RENDER_INTENT_PERCEPTUAL

STEPS TO REPRODUCE
1. Have a HDR display with
2. Open a chromium version containg the mentioned commit
3. Observe it's way too dark

OBSERVED RESULT & EXPECTED RESULT
See the attached comparison image. On the left, the affected version, on the right the unaffected version.

SOFTWARE/OS VERSIONS
Operating System: Manjaro Linux 
KDE Plasma Version: 6.4.5
KDE Frameworks Version: 6.19.0
Qt Version: 6.10.0
Kernel Version: 6.16.12-1-MANJARO (64-bit)
Graphics Platform: Wayland
Processors: 16 × 12th Gen Intel® Core™ i7-12650H
Memory: 32 GiB of RAM (31.0 GiB usable)
Graphics Processor 1: Intel® Graphics
Graphics Processor 2: NVIDIA GeForce RTX 3060 Laptop GPU
Manufacturer: ASUSTeK COMPUTER INC.
Product Name: Vivobook_ASUSLaptop N7601ZM_N7601ZM
System Version: 1.0

ADDITIONAL INFORMATION
Comment 1 Jakub 2025-10-19 12:52:55 UTC 
Another way to reproduce. At 100% brightness, open chromium with affected commit. Open a solid white rgb(255,255,255) background. With color picker, pick the color (I used KColorChooser). The result is #bababa or rgb(186,186,186)
Comment 2 Zamundaaa 2025-10-19 13:48:28 UTC 
Using the perceptual rendering intent is the correct thing to do, but if HDR metadata is wrong, tone mapping can have weird side effects. Chromium really needs to set HDR metadata to match the content, otherwise there will always be problems.
Comment 3 Jakub 2025-10-24 22:45:04 UTC 
Just tested and this issue does not occur on 6.5.0, so I guess its related to improved tonemapping