Examine source code of Tab Position Manager

{
  "manifest_version": 2,
  "name": "Tab Position Manager",
  "version": "1.1",
  "description": "Automatically move a new tab based on URL to a position next to another tab",
  "permissions": [
    "tabs",
    "storage"
  ],
  "options_ui": {
    "page": "options.html",
    "open_in_tab": false
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{19f7f3c3-d544-4356-8eea-e293c1701057}"
    }
  }
}