Examine source code of Google Shia

{
  "name": "Google Shia",
  "description": "Stay motivated everyday !",
  "version": "1.4",
  "manifest_version": 2,
  "content_scripts": [
    {
      "matches": [
        "https://www.google.com/",
        "https://www.google.ca/",
        "https://www.google.fr/"
      ],
      "css": [
        "shia.css"
      ],
      "js": [
        "shia.js"
      ]
    }
  ],
  "web_accessible_resources": [
    "shia.webm"
  ],
  "icons": {
    "16": "icon_16.png",
    "32": "icon_32.png",
    "48": "icon_48.png",
    "128": "icon_128.png"
  }
}