Examine source code of Unouit

{
  "description": "Adds the Unouit browser action icon to the toolbar to store the url on your account at https://www.unouit.com",
  "manifest_version": 2,
  "name": "Unouit",
  "version": "1.5",
  "icons": {
    "48": "icons/logo-48.png"
  },
  "permissions": [
    "https://*/",
    "activeTab"
  ],
  "browser_action": {
    "default_icon": "icons/logo-48.png",
    "theme_icons": [
      {
        "light": "icons/logo-48.png",
        "dark": "icons/logo-48.png",
        "size": 32
      }
    ],
    "default_title": "Unouit 1.4",
    "default_popup": "popup/unouit.html"
  },
  "default_locale": "en"
}