Examine source code of Tab Limiter

{
  "manifest_version": 2,
  "name": "Tab Limiter",
  "version": "0.2.1resigned1",
  "description": "Limit the number of tabs a given window can have (i.e. set a maximum number of tabs on a per-window basis) and automatically open additional tabs in a different window.",
  "author": "Paul Morris",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "incognito": "spanning",
  "permissions": [
    "sessions",
    "menus"
  ],
  "applications": {
    "gecko": {
      "id": "tab-limiter@example.com",
      "strict_min_version": "60.0"
    }
  }
}