Examine source code of Derzan's CryptoWager

{
  "name": "__MSG_appName__",
  "author": "Derzan",
  "version": "0.9",
  "manifest_version": 2,
  "description": "__MSG_appDescription__",
  "icons": {
    "16": "assets/icons/icon-16.png",
    "24": "assets/icons/icon-24.png",
    "64": "assets/icons/icon-64.png",
    "128": "assets/icons/icon-128.png"
  },
  "default_locale": "en",
  "content_scripts": [
    {
      "matches": [
        "http://*/*",
        "https://www.twitch.tv/*"
      ],
      "js": [
        "content/content.js"
      ]
    }
  ],
  "background": {
    "scripts": [
      "background/background.js"
    ]
  },
  "permissions": [
    "<all_urls>",
    "cookies"
  ],
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "54.0a1",
      "id": "{a46db4ed-756d-4f39-aa6e-b5b128d90986}"
    }
  }
}