| Summary: | The background of translucent widgets is brighter than SDR white in HDR mode | ||
|---|---|---|---|
| Product: | [Plasma] kwin | Reporter: | dantmnf <dantmnf2+kdebugs> |
| Component: | effects-various | Assignee: | KWin default assignee <kwin-bugs-null> |
| Status: | CONFIRMED --- | ||
| Severity: | normal | CC: | kde, kdedev, nate, xaver.hugl |
| Priority: | NOR | ||
| Version First Reported In: | 6.3.4 | ||
| Target Milestone: | --- | ||
| Platform: | Other | ||
| OS: | Linux | ||
| Latest Commit: | Version Fixed/Implemented In: | ||
| Sentry Crash Report: | |||
| Attachments: | HDR with Brightness set to 0 | ||
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Description
dantmnf
2025-04-10 17:28:40 UTC
Thanks for the report. Can you provide a link to an SDR white reference image, or let us know what window you're referring to by "Open a window with SDR white for reference"? Also, can you let us know a widget you experienced this with? Thanks. SDR white means color (255, 255, 255) in SDR content, such as css color "white" in web browser. In my case, I experienced this with the default bottom panel and it's popups. I'm not able to reproduce this on git-master with the Breeze theme on an HDR display I used a rectangle filled with 255,255,255 white in mtPaint, as well as a web browser open to a page with white elements as reference and then opened the App Menu next to them. There was no difference in the brightness between the color swatch and the menu search bar when they were Can you share a screenshot of your Display Configuration setting page for the display? Can you also share a screenshot of your settings for the Translucency desktop effect? Thanks Created attachment 180292 [details]
HDR with Brightness set to 0
Further investigation shows this issue happens when the Brightness setting in Display Configuration is not 100, setting Brightness to 0 will get an extreme case.
The Translucency effect is not enabled, disabling the Blur effect doesn't help either.
Thanks for that screenshot, it's very helpful I re-tested on a different system running git-master connected to an HDR monitor and I'm still not able to reproduce it. I do notice a slight difference in how the menu is shown, regarding blur (with transparency disabled in the desktop effects; I tried with blur on and blur off) This could be a difference in Qt (my systems have 6.8.3) or tweaks made by the distribution (I have Solus) What distribution is this system running? I experienced this on 2 Arch Linux systems, with slightly different config. I will test on Fedora live system later. Also reproduced on Fedora 42, with Plasma 6.3.4/KF 6.12.0/Qt 6.8.2, using live system default settings except Plasma theme changed to Breeze Light. Thanks for adding that. I'll let the maintainers who are more experienced with HDR / SDR take it from here. Can confirm; specifically the contrast effect is causing this. |