Examine source code of Smart Tab Grouping V2

{
  "manifest_version": 2,
  "name": "Smart Tab Grouping V2",
  "version": "1.3",
  "description": "Automatically group and organize tabs by user-defined categories.",
  "permissions": [
    "tabs",
    "storage"
  ],
  "background": {
    "scripts": [
      "groupRules.js",
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "browser_action": {
    "default_title": "Smart Tab Grouping",
    "default_icon": "icons/logo_64.png"
  },
  "icons": {
    "32": "icons/logo_32.png",
    "64": "icons/logo_64.png",
    "128": "icons/logo_128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{74441c2a-793a-4473-afa5-ecd40f84c531}"
    }
  }
}