While Firefox "supports" HDR for videos. Firefox's web engine is still SDR.In HDR mode, the Gecko engine needs to become a 48-bit float16 framebuffer (64-bit with float16 alpha), just like Chromium and Webkit already is. From what it seems, it still ...
Safari just added HDR support as part of Technology Preview 125.Chrome 129+ and Safari 125+ now support WebGPU HDR.TestUFO will support WebGPU HDR by late spring or early summer; if FireFox wants a test case.