Examine source code of Containerize Related Tabs

{
  "manifest_version": 2,
  "name": "Containerize Related Tabs",
  "version": "0.0.6",
  "description": "Containerize tabs based on their origin domain",
  "developer": {
    "name": "defkev"
  },
  "applications": {
    "gecko": {
      "id": "containerize-related-tabs@defkev",
      "strict_min_version": "54.0"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html"
  },
  "incognito": "not_allowed",
  "permissions": [
    "contextualIdentities",
    "cookies",
    "management",
    "menus",
    "storage",
    "tabs",
    "theme",
    "webNavigation",
    "<all_urls>"
  ]
}