Examine source code of Trello Organizer

{
  "manifest_version": 2,
  "name": "Trello Organizer",
  "version": "1.0",
  "description": "Save web content to your Trello boards instantly.",
  "permissions": [
    "activeTab",
    "https://api.trello.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "icons": {
    "48": "icon.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{9099f391-0eed-4271-8a53-a7ca5c3f8d62}"
    }
  }
}