Examine source code of RandoMail

{
  "manifest_version": 2,
  "name": "RandoMail",
  "version": "1.0",
  "description": "Sélectionne un mail au hasard dans votre boite mail Gmail",
  "icons": {
    "16": "icons/randomail-16.png",
    "24": "icons/randomail-24.png",
    "32": "icons/randomail-32.png",
    "48": "icons/randomail-48.png",
    "64": "icons/randomail-64.png",
    "72": "icons/randomail-72.png",
    "96": "icons/randomail-96.png",
    "128": "icons/randomail-128.png",
    "512": "icons/randomail-512.png"
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_icon": "icons/randomail-48.png",
    "default_title": "RandoMail",
    "default_popup": "popup/index.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "rems38.dev@gmail.com"
    }
  }
}