The only way to play HDR video natively on Plasma6.2 is installing vk-hdr-layer-kwin6-git from AUR, and append ENABLE_HDR_WSI=1 in /etc/environment, however, if I append ENABLE_HDR_WSI=1 in /etc/environment, the game in gamescope won’t launch.
GPU: AMD RX6750XT
driver: Mesa Gallium driver 24.2.5-arch1.1 for AMD Radeon RX 6750 XT (radeonsi, navi22, LLVM 18.1.8, DRM 3.59
, 6.11.5-zen1-1-zen)