LayoutTests/media/media-source/content/test-opus-manifest.json

{
    "url": "content/test-opus.webm",
    "type": "audio/webm; codecs=\"opus\"",
    "init": { "offset": 0, "size": 272 },
    "duration": 169.001,
    "media": [
        { "offset": 272, "size": 142176, "timestamp": 0, "duration": 10.001 },
        { "offset": 142448, "size": 207102, "timestamp": 80.001, "duration": 10 }
    ]
}