Examine source code of Ultimate YouTube Ad Block

{
  "manifest_version": 2,
  "name": "AdShield - Ultimate Ad Blocker for YouTube",
  "version": "2.76",
  "description": "Block and remove YouTube video ads",
  "permissions": [
    "storage",
    "tabs",
    "webRequest",
    "webRequestBlocking"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.youtube.com/*"
      ],
      "js": [
        "yt.js"
      ],
      "run_at": "document_start"
    }
  ],
  "icons": {
    "16": "icons/16.png",
    "32": "icons/32.png",
    "48": "icons/48.png",
    "64": "icons/64.png",
    "128": "icons/128.png",
    "256": "icons/256.png",
    "512": "icons/512.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "ksa.discount.code@gmail.com",
      "strict_min_version": "109.0"
    }
  }
}