Examine source code of Get Styles

{
  "background": {
    "page": "background.html"
  },
  "content_scripts": [
    {
      "js": [
        "witplugin.js"
      ],
      "matches": [
        "*://*.vk.com/*",
        "*://get-styles.ru/*"
      ]
    }
  ],
  "default_locale": "ru",
  "description": "__MSG_GSExtensionDescription__",
  "icons": {
    "16": "images/16.png",
    "32": "images/32.png",
    "48": "images/48.png",
    "128": "images/128.png"
  },
  "manifest_version": 2,
  "name": "Get Styles",
  "page_action": {
    "default_icon": "favicon.ico",
    "default_title": "__MSG_VKStyles__"
  },
  "permissions": [
    "tabs",
    "*://*.vk.com/*",
    "*://get-styles.ru/*"
  ],
  "version": "1.1.0"
}