The default video player tries hardware decoding
Pull request 15172, merged into quattro, sets hwdec to auto-safe in an mpv config, so the default player can try a hardware decoder and fall back to software. David Heinemeier Hansson said a user's mpv config still wins. The merge is not in version 4.0.4.
mpv is the default player for mp4, mkv, and avi. David Heinemeier Hansson said Omarchy shipped no mpv config, and that mpv's own default sets hwdec to no, so video was decoded on the CPU. The merged file sets hwdec to auto-safe. Hansson describes that as an allow-list of hardware decoders, including VA-API, NVDEC, and Vulkan, with a software fallback. mpv reads the system file first and the user's config after it.
On a Ryzen AI Max+ 395 with a Radeon 8060S, David Heinemeier Hansson reports a 6 s 4K30 HEVC 10-bit clip using 2.91 s of CPU time with software decoding and 0.28 s with hardware decoding through vulkan-copy. Hansson said that with hwdec set to no in the user config, decoding went back to software. David Heinemeier Hansson opened and merged the pull request.