> OpenH264 is only used for WebRTC and, importantly, there's no AAC support (which doesn't matter for WebRTC because you can just use Opus). Firefox uses the OS

> OpenH264 is only used for WebRTC and, importantly, there's no AAC support (which doesn't matter for WebRTC because you can just use Opus). Firefox uses the OS platform's H.264 decoder for video element playback. And Firefox supporting H.264 through the platform decoder came a while before OpenH264 happened.