Examine source code of Fontisto

{
  "browser_action": {
    "default_icon": "assets/images/touch-icon/fontisto-128.png",
    "default_popup": "popup.html",
    "default_title": "Fontisto"
  },
  "description": "iconic font and css toolkit",
  "developer": {
    "name": "kenangundogan"
  },
  "icons": {
    "16": "assets/images/touch-icon/fontisto-16.png",
    "38": "assets/images/touch-icon/fontisto-38.png",
    "48": "assets/images/touch-icon/fontisto-48.png",
    "128": "assets/images/touch-icon/fontisto-128.png"
  },
  "manifest_version": 2,
  "name": "Fontisto",
  "permissions": [
    "activeTab"
  ],
  "short_name": "Fontisto icon font",
  "version": "2.2resigned1",
  "browser_specific_settings": {
    "gecko": {
      "id": "{8d6a6ad9-b7c3-4356-a055-cd6a3a918518}"
    }
  }
}