Examine source code of Tab Folders

{
  "manifest_version": 2,
  "name": "Tab Folders",
  "version": "3.5.1",
  "description": "Injects a resizable left slidebar that lists tabs with saved thumbnails, supports toggle, and import/export.",
  "icons": {
    "48": "icons/icon-48.png",
    "96": "icons/icon-96.png"
  },
  "permissions": [
    "activeTab",
    "tabs",
    "storage",
    "<all_urls>"
  ],
  "browser_action": {
    "default_title": "Toggle Tab Folders"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "content.js"
      ],
      "css": [
        "content.css"
      ],
      "run_at": "document_idle"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{c9345188-2977-4132-a659-f1138b7aa1cb}"
    }
  }
}