Examine source code of Youtube Tabs

{
  "browser_specific_settings": {
    "gecko": {
      "strict_min_version": "58.0a1"
    }
  },
  "background": {
    "scripts": [
      "background.js",
      "storage.js"
    ]
  },
  "browser_action": {
    "browser_style": true,
    "default_title": "Youtube tabs",
    "default_popup": "tabs.html",
    "default_icon": {
      "16": "circle_youtube_16.png",
      "32": "circle_youtube_32.png",
      "64": "circle_youtube_64.png"
    }
  },
  "description": "Auto reproducir videos de youtube",
  "homepage_url": "http://swlozano1111.appspot.com/",
  "manifest_version": 2,
  "name": "Youtube Tabs",
  "permissions": [
    "tabs",
    "alarms",
    "storage",
    "*://www.googleapis.com/*",
    "*://accounts.google.com/*"
  ],
  "version": "2.3"
}