Examine source code of HTML Viewer

{
  "manifest_version" : 3 ,
  "name" : "HTML Viewer",
  "version" : "1.0.0",
  "description" : "HTML Viewer: Views page source code.",
  "action" : {
    "default_popup" : "popup.html",
    "default_icon" : "html_viewer.png"
  },
  "icons" : {
    "128" : "html_viewer.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "girlishgH5oO@hotmail.com",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}