Examine source code of Content settings

{
  "name": "Content settings",
  "version": "2.2",
  "description": "Shows the content settings for the current site.",
  "permissions": [
    "contentSettings",
    "tabs"
  ],
  "browser_action": {
    "default_icon": "contentSettings.png",
    "default_popup": "popup.html"
  },
  "manifest_version": 2,
  "browser_specific_settings": {
    "gecko": {
      "id": "{a28571e2-b61c-43d3-99d8-7c517813f460}"
    }
  }
}