The LTS kernel 6.6.26+ and the stable kernel 6.8.5+ have unresolved i915 driver bugs, which break HDR/DV tone-mapping on Intel 12th gen or newer iGPU / ARC A-series GPUs. Please downgrade to 6.6.25 or 6.8.4 if you are having problems.
Issue: jellyfin/jellyfin#11380