Examine source code of iCloud Manager

{
  "name": "iCloud Manager",
  "description": "Switch to iCloud Dashboard with a single click or customizable keyboard shortcuts!",
  "version": "1.3",
  "manifest_version": 2,
  "permissions": [
    "storage",
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "icons": {
    "48": "icons/icon.png"
  },
  "browser_action": {
    "default_icon": "icons/icon.png",
    "default_title": "iCloud Manager",
    "default_popup": "popup/popup.html"
  },
  "options_ui": {
    "page": "options/options.html"
  },
  "commands": {
    "_i_popup": {
      "suggested_key": {
        "default": "Ctrl+Alt+0"
      },
      "description": "Open iCloud Popup"
    },
    "_icloud_": {
      "suggested_key": {
        "default": "Ctrl+Alt+I"
      },
      "description": "Switch to iCloud Tab"
    },
    "_icloud_home": {
      "suggested_key": {
        "default": "Ctrl+Alt+H"
      },
      "description": "Switch to iCloud Home"
    },
    "_icloud_mail": {
      "suggested_key": {
        "default": "Ctrl+Alt+M"
      },
      "description": "Switch to iCloud Mail"
    },
    "_icloud_contacts": {
      "suggested_key": {
        "default": "Ctrl+Alt+C"
      },
      "description": "Switch to iCloud Contacts"
    },
    "_icloud_calendar": {
      "suggested_key": {
        "default": "Ctrl+Alt+L"
      },
      "description": "Switch to iCloud Calendar"
    },
    "_icloud_photos": {
      "suggested_key": {
        "default": "Ctrl+Alt+O"
      },
      "description": "Switch to iCloud Photos"
    },
    "_icloud_iclouddrive": {
      "suggested_key": {
        "default": "Ctrl+Alt+D"
      },
      "description": "Switch to iCloud Drive"
    },
    "_icloud_notes": {
      "suggested_key": {
        "default": "Ctrl+Alt+N"
      },
      "description": "Switch to iCloud Notes"
    },
    "_icloud_reminders": {
      "suggested_key": {
        "default": "Ctrl+Alt+R"
      },
      "description": "Switch to iCloud Reminders"
    },
    "_icloud_find": {
      "suggested_key": {
        "default": "Ctrl+Alt+F"
      },
      "description": "Switch to iCloud Find My iPhone"
    },
    "_icloud_settings": {
      "suggested_key": {
        "default": "Ctrl+Alt+S"
      },
      "description": "Switch to iCloud Settings"
    }
  }
}