HDR broken using gamescope 3.16.17 on KDE Plasma 6.5.3 on Arch Linux

[aaron-rust]

Is there an existing issue for this?

• I have searched the existing issues

Are you using any gamescope patches or a forked version of gamescope?

• The issue occurs on upstream gamescope without any modifications

Current Behavior

The HDR functionality of gamescope broke because of an update of KDE Plasma on Arch Linux.

The current version of gamescope that is delivered on Arch Linux is gamescope 3.16.17-1 updated on 2025-09-08.
The current version of KDE Plasma on Arch Linux is 6.5.3, updated on 2025-12-09.

There was a change in the code of KDE Plasma that handles HDR some time in the last two months. Since then the old version of gamescope (2025-09-08) is not compatible anymore to use the HDR functionality.

The same developer that changed the code in Plasma also made gamescope compatible again by this commit: 7d4e835

Unfortunately there was no update from gamescope since 2025-09-08, so Arch Linux users now have a broken HDR functionality until gamescope releases a new update or the package on the Arch Repos gets a hotfix update to include the commit mentioned above manually.

A rollback of KDE Plasma to something like 6.5.0 is no viable option to many users as it affects many packages and dependencies. A rollback of gamescope is useless, as the incompatibility didn't come from the change in gamescope, but a change in KDE Plasma.

Steps To Reproduce

1. Start a Wayland Session of KDE Plasma 6.5.3 on Arch Linux
2. Install the newest gamescope version
3. Try to use the --hdr-enabled flag when starting gamescope
   --> HDR does not work. It displays SDR and settings menus in games show HDR als "unavailable".

Hardware information

- Distro: Arch Linux x86_64
- CPU: AMD Ryzen 9 5900X 12-Core Processor
- GPU: Advanced Micro Devices, Inc. [AMD/ATI] Navi 21 [Radeon RX 6800/6800 XT / 6900 XT]
- Driver Version: Mesa 25.3.1-arch1.2

Software information

- Desktop environment: KDE Plasma 6.5.3
- Session type: Wayland
- Gamescope version: 3.16.17
- Gamescope launch command(s), generated by Lutris, starting Cyberpunk 2077, GOG version:
gamescope -w 3840 -h 2160 -W 3840 -H 2160 -f --hdr-enabled --force-grab-cursor -- gamemoderun /home/user/.local/share/lutris/runners/wine/wine-ge-8-26-x86_64/bin/wine /home/user/games/gog/cyberpunk-2077/drive_c/GOG Games/Cyberpunk 2077/bin/x64/Cyberpunk2077.exe

Which gamescope backends have the issue you are reporting?

• Wayland (default for nested gamescope)
• DRM (default for embedded gamescope, i.e. gamescope-session)
• SDL
• OpenVR

Logging, screenshots, or anything else

No response

[admalledd]

In theory, Arch extra/gamescope package just recently updated: https://gitlab.archlinux.org/archlinux/packaging/packages/gamescope/-/commit/f595a8f0ec7a09b3135059501a501d27080fa9a8 to 3.16.18-1

Personally I just tried the gamescope-git AUR package, using (at time of writing) latest git: 3.16.18.r0.g08a4595b-1

However, I still lack the option to enable HDR like I once could (Helldivers 2, via steam)

gamescope --adaptive-sync --hdr-enabled -s 1.5 -f --force-grab-cursor -W 2560 -H 1440 -w 2560 -h 1440 -- %command%

[Thomas-git]

Got the same problem using Fedora 42/Plasma. Compiling Gamescope (3.16.19-4-g221394f) from Source also don't works. @aaron-rust linked commit is not enough to restore HDR.
Maybe something happened on Nvidia side ? Or may be it's a wider problem because Gnome and AMD seems affected too.

[aaron-rust]

@admalledd Yes, the packager of gamescope on Arch asked me to create this issue to create a papertrail upstream to make the issue visible on this level. So the update occuring shortly after I created the issue is no coincidence :)

@Thomas-git I have a working setup again under the following runtime environment, so the problem on Archlinux is fixed. Maybe it helps you to determine the component / configuration that differs on your Fedora system:

• Archlinux system as up to date as it gets on 2025-12-26 23:26

• gamescope 3.16.19-1 https://archlinux.org/packages/extra/x86_64/gamescope/

• KDE Plasma Version: 6.5.4

• KDE Frameworks Version: 6.21.0

• Qt Version: 6.10.1

• Kernel Version: 6.18.2-arch2-1 (64-bit)

• Graphics Platform: Wayland

• Processors: 24 × AMD Ryzen 9 5900X 12-Core Processor

• Memory: 32 GiB of RAM (31,3 GiB usable)

• Graphics Processor: AMD Radeon RX 6900 XT

Under these conditions (and a compatible HDR monitor connected and activated in the Plasma System Settings) I can execute multiple HDR games without a problem: Cyberpunk 2077, Ori and the Will of the Wisps, Shadow of the Tomb Raider, Control, Witcher 3.

I use the following command in Lutris (Steam works as well):

gamescope -w 3840 -h 2160 -W 3840 -H 2160 -f --hdr-enabled --force-grab-cursor -- gamemoderun /home/user/.local/share/lutris/runners/wine/wine-ge-8-26-x86_64/bin/wine /mnt/games/gog/cyberpunk-2077/drive_c/GOG Games/Cyberpunk 2077/bin/x64/Cyberpunk2077.exe

[admalledd]

@aaron-rust no, this still isn't working for me on Arch, I am fully up to date and both gamescope (3.16.19-1) and gamescope-git (221394fe) do not let me select HDR in any of the games I can try (Horzion:FW, HellDivers2, Control all previously worked)

Same versions of other key software you point out:

EDIT: Is there any logs or other reproduction cases I can use to narrow down what is going on?

[aaron-rust]

@admalledd I also tried "Control", and it works like every other HDR title I’ve tested. The HDR option is available in the menu, and I confirmed with my own eyes that bright lights in the game are genuinely blinding. So HDR is both theoretically and practically proven to be active using gamescope 3.16.19 and KDE Plasma 6.5.4. I also tested , "Ori and the Will of the Wisps" and "Deep Rock Galactic" working as well.

As you have the same software versions installed and even a hardware configuration that is nearly identical to mine, I suppose your launch parameters are incorrect. Here are my launch parameters for Steam games:
MANGOHUD=1 gamescope -w 3840 -h 2160 -r 140 -f --hdr-enabled -- %command%

[Thomas-git]

Here is my config

Gamescope 3.16.19-4-g221394f
Operating System: Fedora Linux 42
KDE Plasma Version: 6.5.4
KDE Frameworks Version: 6.21.0
Qt Version: 6.9.3
Kernel Version: 6.17.13-200.fc42.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 16 × 12th Gen Intel® Core™ i5-12600K
Memory: 32 Gio of RAM (31.1 Gio usable)
Graphics Processor: NVIDIA GeForce RTX 5070 Ti
Manufacturer: Micro-Star International Co., Ltd.
Product Name: MS-7D42
System Version: 2.0

And the command line I use in steam (previously worked).
gamescope --hdr-enabled -w 3440 -h 1440 -r 165 -f --adaptive-sync -- %command%

Actually, games don’t show HDR as available. Again, it used to works.

[admalledd]

@aaron-rust again, using exact same arguments (even enabling MangoHud), and in Control, I can't enable HDR:

Again, is there useful logs/ways to test HDR with gamescope that could narrow down what the differences/situation is?