HDR Media Capabilities

Image HDR support coming to Firefox?

MediaCapabilities? implementations are missing features needed to check for feature/playback support on a variety of platforms.

• HDR fields currently ignored by Chrome (seems to be in the works https://chromium-review.googlesource.com/q/MediaCapabilities)
• WebKit? sights fingerprinting issues (Chrome uses `powerEfficient: false` for configurations that require software decoding)
• Dolby needs to join the W3C? to make and move proposals forward
• on PS5?, decodeInfo calls fail after more than 25 calls (synchronous or for the lifespan of the app?)
• What is the state of `transition` support detection? https://github.com/w3c/media-capabilities/blob/main/explainer.md#transitioning-between-stream-configurations

Example use-case

• Badging for DolbyVision? profile 8 metadata usage requires decodeInfo to expose whether `hdrMetadataType` that maps to HLS SUPPLEMENTAL-CODECS attribute is supported (vs ignored).

Should issue be filed here https://github.com/w3c/media-capabilities/issues ?