Examine source code of Video URL to Embed

{
  "manifest_version": 2,
  "name": "Video URL to Embed",
  "version": "2.5.17",
  "default_locale": "es",
  "description": "Alterna entre versión original y video incrustado.",
  "author": "SystemAlex",
  "icons": {
    "16": "./assets/icon16.png",
    "32": "./assets/icon32.png",
    "128": "./assets/icon128.png"
  },
  "permissions": [
    "storage",
    "tabs",
    "notifications",
    "webRequest",
    "webRequestBlocking",
    "https://*/*",
    "http://*/*"
  ],
  "background": {
    "scripts": [
      "js/background.js"
    ],
    "persistent": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "video-url-to-embed@systemalex.com"
    }
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": true,
    "browser_style": true
  },
  "browser_action": {
    "default_icon": "./assets/icon128.png",
    "default_title": "Alterna Vista de Video"
  },
  "content_scripts": [
    {
      "matches": [
        "https://streamtape.com/v/*",
        "https://sendvid.com/*",
        "https://uqload.net/*",
        "https://vidtube.one/*",
        "https://voe.sx/*",
        "https://www.dailymotion.com/*",
        "https://www.youtube.com/*",
        "https://vimeo.com/*",
        "https://vidmoly.me/w/*"
      ],
      "js": [
        "js/functions.js"
      ],
      "run_at": "document_start"
    },
    {
      "matches": [
        "https://streamtape.com/e/*",
        "https://sendvid.com/embed/*",
        "https://uqload.net/embed-*",
        "https://vidtube.one/embed-*",
        "https://voe.sx/e/*",
        "https://jennifercertaindevelopment.com/e/*",
        "https://geo.dailymotion.com/*",
        "https://www.youtube.com/embed/*",
        "https://player.vimeo.com/video/*",
        "https://vidmoly.to/embed-*"
      ],
      "js": [
        "js/functions.js",
        "js/fullscreen.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "js/redirectRules.json",
    "assets/icon128.png",
    "css/bootstrap.min.css"
  ]
}