Examine source code of Twitch Live Rewind

{
  "manifest_version": 3,
  "name": "Twitch Live Rewind",
  "version": "1.3.2",
  "description": "Rewind a Twitch live stream through the growing VOD without reloading the page.",
  "icons": {
    "16": "icons/icon-16.png",
    "32": "icons/icon-32.png",
    "48": "icons/icon-48.png",
    "128": "icons/icon-128.png"
  },
  "permissions": [
    "storage"
  ],
  "host_permissions": [
    "https://*.twitch.tv/*",
    "https://gql.twitch.tv/*",
    "https://usher.ttvnw.net/*",
    "https://*.cloudfront.net/*",
    "https://*.twitchcdn.net/*",
    "https://*.ttvnw.net/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "twitch-live-rewind@example.com",
      "strict_min_version": "109.0",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  },
  "action": {
    "default_title": "Twitch Live Rewind",
    "default_icon": {
      "16": "icons/icon-16.png",
      "32": "icons/icon-32.png",
      "48": "icons/icon-48.png",
      "128": "icons/icon-128.png"
    },
    "default_popup": "popup/popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.twitch.tv/*"
      ],
      "js": [
        "lib/hls.min.js",
        "src/content.js"
      ],
      "css": [
        "src/content.css"
      ],
      "run_at": "document_idle"
    }
  ]
}