Examine source code of Flappy Level Builder

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  "name": "__MSG_extensionName__",
  "version": "1.0.0",
  "description": "__MSG_extensionDescription__",
  "permissions": [
    "storage",
    "activeTab"
  ],
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "48": "icons/icon-48.png",
      "96": "icons/icon-96.png"
    }
  },
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "web_accessible_resources": [
    "images/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{af8bb05f-108e-4b74-bf31-c4854d245a5e}"
    }
  }
}