Examine source code of Google search site

{
  "manifest_version": 2,
  "name": "Google search site",
  "description": "Open google search with site:<tab hostname>",
  "version": "0.0.1",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "tabs"
  ],
  "browser_action": {
    "default_icon": "search-24px-lighttheme.svg",
    "theme_icons": [
      {
        "light": "search-24px-lighttheme.svg",
        "dark": "search-24px-darktheme.svg",
        "size": 24
      }
    ]
  },
  "applications": {
    "gecko": {
      "id": "googlesearchsite@example.com"
    }
  }
}