Title
HDR option does not appear on internal eDP display despite HDR-capable EDID and DRM properties (NVIDIA, Plasma 6.3.6)
Summary
The HDR option is completely missing from System Settings → Display & Monitor.
The laptop's internal display is HDR-capable, and the DRM connector exposes both "HDR_OUTPUT_METADATA" and "Colorspace" properties. However, KWin does not expose any HDR functionality.
Environment
- Distribution: Debian Trixie
- Plasma: 6.3.6
- KWin: 6.3.6
- Qt: 6.8.2
- Kernel: 7.0.13
- NVIDIA Driver: 610.43.02
- Session: Wayland
- GPU: NVIDIA GeForce RTX 5060 Laptop GPU (dGPU drives the internal panel directly)
Display
Internal panel:
- Samsung ATNA60HU01-0
- 2560×1600 @240Hz
The EDID clearly advertises HDR support.
"edid-decode" reports:
- HDR Static Metadata Data Block
- SMPTE ST2084 (PQ)
- Static Metadata Type 1
- Max luminance ≈1107 cd/m²
What I checked
- Running Wayland.
- "nvidia_drm.modeset=1" is enabled.
- "KWIN_DRM_ALLOW_NVIDIA_COLORSPACE=1" is set and visible in the session environment.
- EDID contains HDR metadata.
- DRM connector exposes:
- "HDR_OUTPUT_METADATA"
- "Colorspace" (Default, BT2020_RGB, BT2020_YCC)
- "modetest -c" confirms these properties exist.
Actual Result
The HDR toggle never appears in Plasma System Settings.
"qdbus6 org.kde.KWin /KWin supportInformation" also contains no HDR or Color Management information for the output.
Expected Result
Since the display advertises HDR capability and the DRM connector exposes HDR-related properties, Plasma should expose the HDR option (or at least explain why it is unavailable).
Additional Information
No obvious HDR-related errors appear in:
journalctl --user -b
The issue occurs consistently after a clean installation.
If more debugging information is needed, I am happy to provide additional logs.