Examine source code of Unsafe Container

{
  "manifest_version": 2,
  "name": "Unsafe Container",
  "version": "0.0.2resigned1",
  "description": "Unsafe Container is based on the Multi-Account Container addon and places all your web activity in a container named \"unsafe container\" and allows you to move it afterwards.",
  "icons": {
    "48": "icon.png",
    "96": "icon@2x.png"
  },
  "applications": {
    "gecko": {
      "id": "unsafe-container@bmoine.fr",
      "strict_min_version": "57.0"
    }
  },
  "homepage_url": "https://git.bmoine.fr/unsafe-container-firefox",
  "permissions": [
    "<all_urls>",
    "contextualIdentities",
    "cookies",
    "management",
    "tabs",
    "webRequestBlocking",
    "webRequest"
  ],
  "background": {
    "scripts": [
      "app.js"
    ]
  }
}