Examine source code of switch-searcher

{
  "description": "A Search engine switcher toggles between Baidu and Google without re-enter the keywords.",
  "manifest_version": 2,
  "name": "switch-searcher",
  "version": "1.2resigned1",
  "homepage_url": "https://github.com/mdn/webextensions-examples/tree/master/open-my-page-button",
  "content_scripts": [
    {
      "matches": [
        "*://www.google.com/*",
        "*://www.google.com.hk/*"
      ],
      "js": [
        "hook_google.js"
      ]
    },
    {
      "matches": [
        "*://www.baidu.com/*"
      ],
      "js": [
        "hook_baidu.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{c0abcf62-0d82-4703-802b-0c31d1d625cd}"
    }
  }
}