Examine source code of YouTube to Watch2gether

{
  "author": "JayKayUk",
  "background": {
    "scripts": [
      "src/background-script.js"
    ],
    "persistent": false
  },
  "browser-action": {
    "browser-style": true,
    "default-icons": {
      "16": "icons/main-icon-16.png",
      "32": "icons/main-icon-32.png",
      "64": "icons/main-icon-64.png"
    },
    "default-title": "YTtoW2G"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "jaykayuk@email.email"
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.youtube.com/*"
      ],
      "css": [
        "src/yt/style.css"
      ],
      "js": [
        "src/yt/main.js"
      ]
    },
    {
      "matches": [
        "https://w2g.tv/*/room/*"
      ],
      "js": [
        "src/w2g/main.js"
      ]
    }
  ],
  "description": "Adds a button which sends YT videos to open W2G session",
  "developer": {
    "name": "JayKayUk",
    "url": "https://github.com/JayKayUk"
  },
  "homepage_url": "https://github.com/JayKayUk/YTtoW2G-firefox",
  "icons": {
    "48": "icons/main-icon-48.png",
    "96": "icons/main-icon-96.png"
  },
  "manifest_version": 2,
  "name": "YouTube to Watch2gether",
  "permissions": [
    "tabs"
  ],
  "version": "1.0.3",
  "web_accessible_resources": [
    "icons/main-icon-48.png"
  ]
}